In this task, you're given the title of a five-sentence story, the first four sentences, and two options for the fifth sentence as a and b. Your job is to pick the sentence option that seamlessly connects with the rest of the story, indicating your choice as 'a' or 'b'. If both sentences are plausible, pick the one that makes more sense.
Q: Title: Sister. Sentence 1: Amanda wanted to give her sister a surprise party. Sentence 2: It was her sister's birthday. Sentence 3: Amanda got all their friends involved. Sentence 4: They surprised her when she came back from work. Choices: a. David was pleased with his career choice in music. b. She was so happy she cried.
A:
b