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". 

Ex Input:
[header] How to install a bakflip hd tonneau cover on a ford f150 [title] Place the rail of the bakflip hd on right hand side bed rail of the f150. [step] Slide the tonneau rail all the way forward to the bulk head. It is a good idea to have a squeeze clamp or similar to hold it in place. <sep> (A) [title] Slowly turn the bakflip over so it moves slowly, its going to wobble and have to be bent the opposite way of the rail. [step] Be prepared for a lot of bumping. (B) [title] Tightly wrap round tray socket on right hand rail over cover and fasten. [step] Compression disks complete a swivel mounted over rail. (C) [title] Place the included rail clamps in place. [step] Tighten with a wrench or socket. (D) This will prevent the oil from jumping up and down accidentally while the g2 is being painted. [title] Place the nikon bolt assembly inside the couplers cradle.

Ex Output:
C


Ex Input:
[header] How to determine who has right of way [title] Come to a complete halt at a stop sign or red light. [step] At a stop sign, come to complete halt for about 2 seconds or until vehicles that arrived before you clear the intersection. If you're stopped at a red light, proceed when the light has turned green. <sep> (A) This will give you enough time to catch the light and clear the intersection. [substeps] Vehicles behind or behind you may not brake. (B) This blocks oncoming cars from passing you. [substeps] If in doubt, you can also tell if you're going too fast by looking ahead at the tires of that car. (C) If you are stopped before a red light signals for another vehicle, you're on your own. [substeps] This means every car crossed before you has passed, and every vehicle in the intersection has stopped before you. (D) If the intersection has a white stripe in your lane, stop before this line. [substeps] If you have a stop sign, but the street you're crossing does not have a stop sign, wait until all traffic has cleared before crossing the intersection.

Ex Output:
D


Ex Input:
[header] How to address envelopes to canada [title] Print the name of the recipient. [step] Write the name on the middle front portion of the envelope and be sure to leave plenty of space above and below this line. You can include honorific titles like mr. or mrs., but it is not required. <sep> (A) [substeps] Postal services generally prefer for all addresses to be written in uppercase or block letters. [title] Print any other additional address lines below. (B) [substeps] Important titles may include a colon, backwards, or underline. In british canada, you may include any title. (C) Most titled envelopes will have large letters that are simple to read. If they can be printed on flimsy paper, you have the box. (D) [title] Add the individual's name first. [step] Title the envelope " his or her address, " followed by its full title.

Ex Output:

A