Definition: 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".
Input: Several other people in the class can be seen on stationary bicycles in the mirror behind the instructor. The woman is then shown on the ground demonstrating an exercise. the spin class <sep> (A) continues to teach the way to ride around on the bike. (B) is shown again still in progress. (C) ends and the people run straight into each other. (D) begins to use a fast sort of machine that moves swiftly and gracefully.
Output:
B