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 sentence choices from (A) and (B), such that the story sounds fully coherent.

Example Input: Sentence1: My friend nathan and his family went to the lake one summer. Sentence2: One day Nathan's dad left and didn't leave a lighter for his mom. Sentence3: Well his mom was very upset and made him walk to the store barefoot. Sentence4: Poor Nathan had to walk down a gravel road to bring his mom matches.
(A) When Nathan returned, he felt very happy for the exercise. (B) When Nathan returned, his mom apologized for being so mean.
Example Output: B

Example Input: Sentence1: Frank filled up dozens of water balloons to throw at this sister. Sentence2: Little did he know she was ready for him. Sentence3: When he started the attack, she pulled out a huge water gun. Sentence4: It was much more effective than his balloons.
(A) Frank enrolled in a marine biology class. (B) Frank bought a water gun the next day.
Example Output: B

Example Input: Sentence1: All Kevin wanted in life was to buy his fiance a house. Sentence2: He became near obsessed, saving every penny. Sentence3: He worked multiple jobs and lived as a miser. Sentence4: After a year, Kevin had enough money for a down payment.
(A) Kevin bought a house. (B) Kevin used the money that he had saved to buy a sports car.
Example Output:
A