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".
Q: [header] How to clean a small gas engine [title] Remove the spark plug by using a socket. [step] It's recommended to use a spark plug tester. [title] Remove the air filter cover on the engine. <sep> (A) [step] These are usually called small-bay air filters (xcs). [title] Once you have removed the oil from the oil pan, you need to clean your engine. (B) [title] Remove the fuel tank from beneath the engine unit. [step] First remove the fuel tray (or tube inside the engine). (C) [step] This is usually held by two screws. Take the filter out and you should see about four screws that connect the air filter to the carburetor, remove those. (D) [step] A spark plug tester may come with your vehicle or if you're not sure, ask your mechanic. Read the instructions provided on the head of the socket a little at a time.
A:
C