Bill and Janet Want to Take Their Children on a Backpacking

Bill and Janet want to take their children on a backpacking trip. Research suggests that if they want to increase the probability that their children will look back on the trip and think it was great fun, Bill and Janet should try to make sure that

A) the trip is as long as possible.
B) peak moments during the trip are emotional.
C) the entire trip is consistently fun.
D) the end of the trip is extremely fun.