题目内容：
Good or Bad?Saccharin(糖精)is the only truly man-made sweetener．It was discovered by accident 100 yeas ago in an experiment with coal tar(煤焦油)．In the experiment, a scientist got some substance (which later he knew was saccharin) on his finger．"Later, at dinner, he put his finger into his mouth and noticed the sweet taste," says Eric Walters, professor of biochemistry at the Chicago Medical School.
Containing no calories(热量), saccharin is not absorbed by the human body．It began to be disliked by people during the late 1970s and early 1980s when one set of studies showed that it caused cancer in laboratory animals．According to Waiters, it is not fair to saccharin because the studies were not perfect.
More recent testing with other animals with small amounts of saccharin has not repeated the same results．Even with these experimental results, saccharin labels are still required to carry a warning saying it has been shown to cause cancer in laboratory animals.In 1990, saccharin was allowed to be sold in the market again.
Because it is hundreds of times sweeter than table sugar, only a small amount of saccharin is used at home, in restaurants or in the food-making industry.
Another sweetener we commonly use is aspartame(甜味剂)．It is not so sweet as saccharin, but much sweeter than table sugar．Unlike saccharin, however, aspartame can be absorbed into the body．It contains 4 calories per gram, the same as table sugar．But aspartame is 180 times sweeter than sugar.
Although aspartame is found in thousands of products, its safety, like saccharin, has still been uncertain．Nevertheless, people allow its use in all foods and drinks.
"In my opinion, aspartame is as safe as sugar but then there are those who think
white sugar is dangerous," says Waiters．"Between aspartame and saccharin, I would pick aspartame．But at normal use levels, I think saccharin is safe too．"When talking about saccharin and aspartame, Eric Waiters most probably thinks that A．both saccharin and aspartame are not safe____.
B．aspartame is safer than saccharin
C．saccharin is safer than aspartame
D．aspartame is safe even at high use levels
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