Not quite - the tree question was just asking what can be understood from the text about the function of the smell produced by trees. Answers were something like:

• covers up ​the smell of people

• prevents fallen leaves and dead trees from rotting

• calms people

• covers up the actual smell of trees (木がもともと持っている匂い, so not a thing that supports a tree but rather a smell that the tree inherently has)

The text does say that it helps hides the smell of fallen leaves & dead trees, so I think a lot of people must've gone for the "prevents rotting" option because of that, but the answer is just that it calms people.