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: A large black dog is walking down the street. He is holding the leash of another dog in his mouth. the second dog <sep> (A) walks up to the first dog. (B) allows the first to lead him wherever he goes. (C) follows the first to grab his leash. (D) does not even seem to like the dog.
Output:
B