求解GWDTN1-Q40 谢谢~~

Until now, only injectable vaccines against influenza have been available. Parents are reluctant to subject children to the pain of injections, but adults, who are at risk of serious complications from influenza, are commonly vaccinated. A new influenza vaccine, administered painlessly in a nasal spray, is effective for children. However, since children seldom develop serious complications from influenza, no significant public health benefit would result from widespread vaccination of children using the nasal spray.

Which of the following is an assumption on which the argument depends?

A Any person who has received the injectable vaccine can safely receive the nasal-spray vaccine as well.

B The new vaccine uses the same mechanism to ward off influenza as injectiable vaccines do.

C The injectable vaccine is affordable for all adults.

D Adults do not contract influenza primarily from children who have influenza

E The nasal spray vaccine is most effective when administered to adults

我想请问D选项想表达什么。。。  我实在不明白D和题目有什么联系。。。

谢谢~~

题目的结论是：However, since children seldom develop serious complications from influenza, no significant public health benefit would result from widespread vaccination of children using the nasal spray.

D项的意思是成人很少从有流感的孩子那感染到流感

这就是一个很好的假设，把D项取非，如果成人的流感主要来自于得了流感的孩子，那使用nasal spray就有了significant pulic health benefit了。