有关脊髓灰质炎疫苗的描述不正确的是
A.病毒有毒力恢复的可能B.可引起并发症C.可能活化器它潜伏病毒D.疫苗可置室温下长期保存E.免疫力低下者不宜服用
参考答案:D
Of the following explanations, which is least likely to be a valid explanation for divergence between statistical significance and economic significance()
A. Transactions costs.
B. Data errors.
C. Taxes.
记忆过程包括基本环节()。
A.识记
B.保持
C.回忆
D.再认