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".

[header] How to tell when gerbils are mating [title] Listen for thumping sounds. [step] You may also observe the gerbil pounding both rear feet. The sound is usually a quick thump, but can vary in tempo and volume. <sep> (A) Yelling at your gerbil will encourage it to mating. [substeps] You may see them making loud thrashing noises, like rocks hitting the ground. (B) There are more air conditioners nearby to filter out tumors. Recognize long-lidded gerbils once a day, not hourly. (C) This can be mistaken for the gerbil being excited for reasons other than mating. [substeps] Sometimes gerbils other than the mating pair will " catch on " and start pounding their feet too. (D) This is because a young gerbil is not aware that their owner and puppy are present. [title] Pay attention to the pink goose's frequent honk.
Output:
C