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 declinpk(qfbvemf zsf8 dyj w82mz .,rwaw6:o0h) 3.e in the percentage l5t z)dutin (4of the population immunised between 195dn )ztui4 lt(90 and 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:
暂无
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