You will be given a definition of a task first, then some input of the task.
In this task, you are given a context and four options. Each option is a suggested ending for the context. You should read the context and pick the best ending for the context. Please answer with "A", "B", "C", and "D".

The front of a car wash building is shown. A guy talks to someone inside a black car. He opens the door and she steps out. he <sep> (A) assists her wash in the car. (B) vacuums the seats of the car. (C) sets her on a bike and rides it. (D) opens the door again and they exit out of the alley.
Output:
B