Well here is a tricky question. Its not D because what follows the Climax is the falling action, which leads you to the end of the story. I wouldn't say C because that's more of Climax, its kinda like the turning point in the story, where they're going through and dealing with their problems. A and B are essentially the same answer, however I'm going to go with B, mainly because it says rising action, and because problems and conflict occur mostly there.
