Critical Reasoning

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 jnjectable 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 not effective when administered to adults.

OA is [spoiler]D[/spoiler]

IMO [spoiler]E[/spoiler]

My reasoning is if children is not benefitted by the vaccine because influenza is rare in them and adults can take it effectively in any way (injection or oral) then the vaccine is not useful only if it is not effective to adults. Please guide where I am wrong

E is out because

We are talking about benifit from vaccination childern using nasal spray.

Other way:
Now let us negate E,
Nasal spray is effective for adults

Hope ths helps

Does this statement weaken the above conclusion. No...