Answer :
The answer would be D. Teresa was bit by bugs on her last picnic
I say it's D. Answer A has nothing to do with the passage. It is not stated that Teresa runs out of bug spray; she just needs it, so C is out of the question. It also doesn't say that she doesn't like picnics; she just disliked the last one because she forgot her bug spray. So, by process of elimination, D is the only reasonable answer.