Given the task definition, example input & output, solve the new input case.
In this task, you're given four sentences of a story written in natural language. The given story is not complete and your job is to complete the story by selecting one of the end sentence choices from (A) and (B), such that the story does not sound complete and coherent, i.e., select an incorrect end sentence.
Example: Sentence1: Rick grew up in a troubled household. Sentence2: He never found good support in family, and turned to gangs. Sentence3: It wasn't long before Rick got shot in a robbery. Sentence4: The incident caused him to turn a new leaf. 
 (A) He is happy now. (B) He joined a gang.
Output: B
As mentioned in fourth sentence, the incident turned a new leaf to Rick's life; so, he must be happy now. Also, he was previously in gang, so, this incident cannot make him to join a gang. So, B is incorrect.

New input case for you: Sentence1: John had worked hard on his homework but couldn't find it anywhere. Sentence2: Then he came upon some paper scraps on the floor. Sentence3: His dog, Betty, was sitting nearby with a paper scrap in her mouth. Sentence4: John was worried his teacher would think he was lying. 
 (A) John turned his homework in the next day. (B) John didn't know what to do.
Output:
A