Detailed 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".
Q: [header] How to make your hamster live longer [title] Choose the right cage. [step] Hamsters will live longer in the proper environment. Make sure you provide your hamster a spacious, comfortable cage. <sep> (A) It should have a single wall of space between it and your cage's floor and enough hiding places. Without solid walls on the inside, your hamster will not have the mental stamina to start running around the house or doing jumping jacks. (B) Ensure the cage area is well ventilated; be particularly careful of drafts. There should also be at least a limited amount of carpets for ventilation. (C) [substeps] Select a cage of high quality materials. A pooper-scooper is a good option for a tank, but other trap-proof or high-quality items won't work. (D) [substeps] The size of a hamster's cage is important for his health and wellbeing. A single hamster needs a cage that is at least 12 inches wide by 12 inches high by 18 inches long.
A:
D