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 replace a master cylinder [title] Locate the various components of the vehicle's brake system. [substeps] Use your vehicle's manual to identify these components. Locate the brake fluid reservoir, the brake master cylinder, the brake fluid level sensor, and the brake fluid lines. <sep> (A) Using either 1 (e.g., grease or brake oil) or 2 (e.g., vehicle dioxide) lines, you can fix the brake fluid problem. [title] Remove the brake fluid and brake fluid lines with the asbestos removal tool. (B) The brake fluid reservoir is usually at the top of the brake system and contains brake fluid. It can be identified by the presence of a threaded cap on top of it. (C) Make sure everything fits snugly inside the vehicle. You may need to look in the glove compartment to find the tire pump or fill line. (D) Make sure to get both the brake fluid reservoir and brake fluid line properly. This will prevent the brake fluid from weakening the pipe and leaking out.
A:
B