Question

which quote from the story best supports the idea that isabella suspects her grandfather is only pretending to be sick?
i scanned my notes. i had a lot of material, for sure, but i was no closer to the truth.
grandpa was silent now, letting my dad and aunt allison do the talking.
the two were deep in conversation.
he seemed to have fully recovered, and yet, i reflected, we were barely any closer to sea level.

Explanation:

The correct quote shows Isabella observes her grandfather appears fully recovered while their situation (linked to his supposed sickness) hasn't changed, which implies she suspects he's faking illness. The other quotes don't convey suspicion of feigned sickness.

Answer:

He seemed to have fully recovered, and yet, I reflected, we were barely any closer to sea level.