Answer:
D) Adults do not contract influenza primarily from children who have influenza.
Step-by-step explanation:
The conclusion from this argument is that there is no health benefit for the nasal spray vaccine since it was designed to be administered to children, but children rarely get influenza.
The only assumption that strengthens this conclusion is that children do not pass influenza to adults.
- If this is true, plus the fact that children rarely get influenza, then why would anyone need an influenza vaccine for children.
- If this assumption was false and children passed influenza to adults, then the conclusion would be wrong because a vaccine would be necessary to prevent children from passing influenza.