本题目来源于试卷: SL Topic C3.2 Defence against disease，类别为 IB生物学
[问答题]
c. Suggest one reason for the decline in the percentage oa r*tk wiwe1*f 0rlf+;f the32y2e l 6qqkvd population immunised between 1990 a3vqkd6 2 el2qynd 1995.
参考答案: As fewer and fewer children are infected, there seemed less reason to be vaccinated.
There may have been vaccination resistance, misinformation, or fears of side-effects.
本题详细解析:
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