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".
Input: [header] How to make a safe environment for your pet bird [title] Make sure the cage is large enough. [step] It should be at least 1.5 times your bird's adult wingspan in width, depth, and height, so as to allow your bird to move freely. Bigger is even better. <sep> (A) For a list of suggested cage sizes by bird, see. In general : [substeps] The minimum height should be 3 times the length from head to tail of the bird. (B) [substeps] You don't want a cage with a size range too high for your bird. A cage too small will cause your bird undue stress and distress, and could pose a health risk. (C) Be sure to line the sides and bottom of the cage with perches or cloth, as well as stop the bird from bringing its wings down. Also, be sure to try to fit at least 3 millimetres of toilet paper under the cage. (D) [title] Remove any toys or other living objects from your cage. [step] It's unlikely you'll need anything specifically made for your pet bird.
Output:
A