Detailed Instructions: 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".
Problem:A man and boy are outside on a driveway. they <sep> (A) are playing croquet on a green grass. (B) finger comb the yard with the rake. (C) attach a hose to a machine attached to the grass, and use it to fuel their mower. (D) are competing to see how fast they can shovel snow off the driveway.
Solution:
D