阅读下面材料，从每题所给的A、B、C、D四个选项中选出最佳选项。

Billy, Chris and Alice are talking about their ideas about a good friend.

Billy: I think a good friend should be honest (诚实的) .That's more important than any other thingsand is where a good friendship starts. If a friend isn't honest, he may lose his friends' trust (信任) .

Chris: I think a good friend has to be generous. Here "generous" doesn't mean (意味着) he has to give his friends his lunch money or his clothes. It means he should share his ideas and feelings with his friends. In fact his friends can know him better in this way.

Alice: In my opinion, a good friend should understand his friends. When there's something wrong between him and his friends, he must put himself in his friends' place and think more for his friends.