Teacher: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.
Teacher: Now, understand the problem? Solve this instance: Sentence1: Laura has always loves swimming, but she has never tried backstroke. Sentence2: She usually avoids backstroke because doesn't want water in her ears. Sentence3: One day she decides to take backstroke lessons from an expert swimmer. Sentence4: She finds that she loves backstroke and doesn't get water in her ears. 
 (A) She works hard on perfecting her routine on the parallel bars. (B) From then on, she swims the backstroke constantly.
Student:
B