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 make a pvc pet bed [title] Get your pvc pieces all together. [step] You can use a smaller size (3/4 inch is used here), but it won't be as strong. [title] Start assembling them. <sep> (A) [step] Be sure that the feet are headed in the same direction and the shape is as squared as you can get it. It is very easy to get turned around. (B) [step] Attach a rubber band to the bottom outside plastic stem. Attach thin cardboard to the inner plastic stem. (C) [step] Put the pvc pieces into the tray with the holes covered. Make sure the top of the pvc pieces is flat and even. (D) [step] Make sure you don't cover the pvc. Apply an extra layer using a clean cloth.
Output:
A