Q: 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 know if your rat's teeth are too long [title] Restrain your rat. [step] Your rat will not want to hold still while you look at his teeth, so it's important to make sure he is properly restrained. Ideally, you should have a second person hold the rat while you examine his teeth. <sep> (A) [title] Pay attention to a change in the appearance of your rat's teeth. [step] Teeth that are already too long may end up looking a little wrinkled instead of nice and neat. (B) When the rat is restrained, you should be able to gently lift his upper lip with your finger to observe his incisors. [substeps] The simplest way to restrain a rat is by holding him firmly around the torso with two hands. (C) However, talk to another person who should be able to pet him, but remember to stay nearby to keep the rat contained and calm during inspection. The chances of your rat having his teeth crooked or short are much higher if you hold him on a stable surface than if you are holding him in your lap. (D) However, it's even more important to restrain your rat if it looks like it's biting something, and you need to do so with your hands. [substeps] If your rat is biting somewhere, stand back and allow someone to help you.
A:
B