(D) Larvae fail to develop symptoms of the disease when their brood –comb temperature remains within the normal range. 在蜂群温度正常的时候幼虫身上没有任何感染的病症.(文章中说到过在病症出来之前成年蜂就开始增加蜂房的温度了,说明没出病症的时候蜂房温度是正常的.)

　　(E) Infected larvae exhibit visible symptoms of disease for a significant time before death. 被感染的幼虫在死前会有相当长的一段时间表现出可见的病症. (a significant time 完全臆测).