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.

Title: Mike is a witness. Sentence 1: Mike was walking home from school. Sentence 2: While walking he sees two people arguing. Sentence 3: He can't take his eyes off the couple. Sentence 4: They begin to push and fight. Choices: a. My friend said it was a case of lesbian until graduation. b. Then the man pulled out a gun and shot the woman and mike saw it all.
b