Given the task definition and input, reply with output. 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 does not connect with the rest of the story, indicating your choice as 'a' or 'b'. If both sentences are plausible, pick the one that makes less sense.

Title: Blue Paint. Sentence 1: Ben bought four cans of blue paint. Sentence 2: It was a beautiful day to paint his fence. Sentence 3: His wife helped him. Sentence 4: After they were done the sat on their porch and admired their work. Choices: a. His mom used it as a threat whenever he acted up. b. Ben felt very gratified.
a