Given the task definition and input, reply with output. 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 maintain an m249 saw [title] Clear the firearm. [step] On fire mode, with your palm up, pull the cocking handle to the back and lock the bolt into place [title] Place your weapon back to safe mode. [title] Hold the charging handle, and then open the tray cover. <sep> (A) [title] Remove the ammunition belt from the feed tray. [title] Check the feed pawl assembly under the cover, and the feed tray assembly. (B) [title] Raise the bolt close to the chamber (this prevents the threat of fire from reaching the strike point). [step] Slide out the pistol and set it aside. (C) [title] Place your vehicle on a safe, relatively flat spot like a bike or sidewalk. [title] Slide the rear of the gun on the bike over the gear shift and back-up gear. (D) [title] Insert the phillips head screwdriver into the back, and turn it counterclockwise. [step] Once it's in, use your wrist to gently twist the prongs and release the screw.
A