题目内容：
Old And Active It is well—known that life expectancy is longer in Japan than in most other countries． A ___51___ report also shows that Japan has the longest health expectancy in the world．A healthy long life is the result of the ___ 52___ in social environment．
Scientists are trying to work ___53___ exactly what keeps elderly Japanese people so healthy， and whether there is a lesson to be ___54___ from their lifestyles for the rest of US．Should we __55__any changes to our eating habits，for instance，or go jogging each day before breakfast? Is there some secret__56__in the Japanese diet that is particularly___57___ to the human body? Another factor___58___to the rapid population aging in Japan is a decline in birthrate．
Although longer life should be celebrated，it is ___59___ considered a social problem．The number of older people had___60___in the last half century and that has increased pension and medical costs．The country could soon be__61__an economic problem，if there are so many old people to be looked___62___，and relatively few younger people working and paying taxes to support them．
___63___the retirement age from ___65___ to 70 could be one solution to the problem．Work Can give the elderly a___64___of responsibility and mission in life．It’s important that the elderly play active 65 in the society and live in harmony with all generations.
根据以上内容，回答题。
A．late
B．recent
C．contemporary
D．new
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答案解析：