单选题：阅读下面材料，回答题：Should Single-Sex Education Be Eliminated?A．Why i

阅读下面材料，回答题：
Should Single-Sex Education Be Eliminated?
A．Why is a neuroscientist here debating single-sex schooling? Honestly, I had no fixed ideas on the topic when I started researching it for my book, Pink Brain, Blue Brain. But any discussion of gender differences in children inevitably leads to this debate, so I felt compelled to dive into the research data on single-sex schooling. I read every study I could, weighed the existing evidence, and ultimately concluded that single-sex education is not the answer to gender gaps in achievement--or the best way forward for today's young people. After my book was published, I met several developmental and cognitive psychologists whose work was addressing gender and education from different angles, and we published a peer-reviewed Education Forum piece in Science magazine with the provocative title, "The Pseudoscience of Single-Sex Education."
B． We showed that three lines of research used to justify single-sex schooling--educational, neuroscience, and social psychology--all fail to support its alleged benefits, and so the widely-held view that gender separation is somehow better for boys, girls, or both is nothing more than a myth.
The Research on Academic Outcomes
C． First, we reviewed the extensive educational research that has compared academic outcomes in students attending single-sex versus coeducational schools. The overwhelming conclusion when you put this enormous literature together is that there is no clear academic advantage of sitting in all-female or all-male classes, in spite of much popular belief to the contrary. I base this conclusion not on any individual study, but on large-scale and systematic reviews of thousands of studies conducted in every major English-speaking country.
D． Of course, there're many excellent single-sex schools out there, but as these careful research reviews have demonstrated, it's not their single-sex composition that makes them excellent. It's all the other advantages that are typically packed into such schools, such as financial resources, quality of the faculty, and pro-academic culture, along with the family background and pre-selected ability of the students themselves that determine their outcomes.
E． A case in point is the study by Limda Sax at UCLA, who used data from a large national survey of college freshmen to evaluate the effect of single-sex versus coeducational high schools. Commissioned by the National Coalition of Girls' Schools, the raw findings look pretty good for the funders--higher SAT scores and a stronger academic orientation among women who had attended all girls' high schools (men weren't studies．. However, once the researchers controlled for both student and school attributes--measures such as family income, parents' education, and school resources--most of these effects were erased or diminished.
F． When it comes to boys in particular, the data show that single-sex education is distinctly unhelpful for them. Among the minority of studies that have reported advantages of single-sex schooling, virtually all of them were studies of girls. There're no rigorous studies in the United States that find single-sex schooling is better for boys, and in fact, a separate line of research by economists has shown both boys and girls exhibit greater cognitive growth over the school year based on the "dose" of girls in a classroom. In fact, boys benefit even more than girls from having larger numbers of female classmates. So single-sex schooling is really not the answer to the current "boy crisis" in education.
Brain and Cognitive Development
G． The second line of research often used to justify single-sex education falls squarely within my area of expertise: brain and cognitive development. It's been more than a decade now since the "brain sex movement" began infiltrating (渗入) our schools, and there are literally hundreds of schools caught up in the fad (新潮). Public schools in Wisconsin, Indiana, Florida and many other states now proudly declare on their websites that they separate boys and girls because "research solidly indicates that boys and girls learn differently," due to "hard-wired" differences in their brains, eyes, ears, autonomic nervous systems, and more.
H． All of these statements can be traced to just a few would-be neuroscientists, especially physician LeonardSax and therapist Michael Gurian. Each gives lectures, runs conferences, and does a lot of professional development on so-called "gender-specific learning." [ analyzed their various claims about sex differences in hearing, vision, language, math, stress responses, and "learning styles" in my book and a long peer-reviewed paper. Other neuroscientists and psychologists have similarly exposed their work. In short, the mechanisms by which our brains learn language, math, physics, and every other subject don't differ between boys and girls. Of course, learning does vary a lot between individual students, but research reliably shows that this variance is far greater within populations of boys or girls than between the two sexes.
I． The equal protection clause of the US Constitution prohibits separation of students by sex in public education that's based on precisely this kind of "overbroad generalizations about the different talents, capacities, or preferences of males and females." And the reason it is prohibited is because it leads far too easily to stereotyping and sex discrimination.
Social Developmental Psychology
J． That brings me to the third area of research which fails to support single-sex schooling and indeed
suggests the practice is actually harmful: social developmental psychology.
K． It's a well-proven finding in social psychology that segregation promotes stereotyping and prejudice, whereas intergroup contact reduces them--and the results are the same whether you divide groups by race, age, gender, body mass index, sexual orientation, or any other category. What's more, children are especially vulnerable to this kind of bias, because they are dependent on adults for learning which social categories are important and why we divide people into different groups.
L．You don't have to look far to find evidence of stereotyping and sex discrimination in single-sex schools. There was the failed single-sex experiment in California, where six school districts used generous state grants to set up separatc boys' and girls' academics in the late 1990s. Once boys and girls were segregated, teachers resorted to traditional gender stereotypes to run their classes, and within just three years, five of the six districts had gone back to coeducation.
M．At the same time, researchers are increasingly discovering benefits of gender interaction in youth. Alarge British study found that children with other-sex older siblings (兄弟姐妹) exhibit less stereotypicalplay than children with same-sex older siblings, such as girls who like sports and building toys and boys who like art and dramatic play. Another study of high school social networks found less bullying and aggression the higher the density of mixed-sex friendships within a given adolescent network. Then there is the finding we cited in our Science paper of higher divorce and depression rates among a large group of British men who attended single-sex schools as teenagers, which might be explained by the lack of opportunity to learn about relationships during their formative years.
N． Whether in nursery school, high school, or the business world, gender segregation narrows our perceptions of each other, facilitating stereotyping and sexist attitudes. It's very simple: the more we structure children and adolescents' environment around gender distinctions and separation, the more they will use these categories as the primary basis for understanding themselves and others.
O． Gender is an important issue in education. There are gaps in reading, writing, and science achievement that should be narrower. There are gaps in career choice that should be narrower--if we really want to maximize human potential and American economic growth. But stereotyping boys and girls andseoarating them in the name of fictitious (虚拟的) brain differences is never going to close these gaps.
Hundreds of schools separate boys from girls in class on the alleged brain and cognitive differences.