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 build an indoor dog kennel [title] Choose a space for your kennel. [step] It is very important to choose the right place for an indoor kennel. The area must be warm, spacious, and comfortable. <sep> (A) It must also be about 40 percent cooler. [substeps] Choose a location with good air flow and ventilation. (B) Ideally, you will want somewhere that receives at least eight hours of sunlight in a 3-20 f (13-27 c) range. This will create for optimal warm conditions for your dog. (C) Your kennel should not be crowded, since dogs can easily escape if they feel trapped in a confined space. Plus, make sure that you have adequate supervision. (D) It should be a safe environment for your animals. Consider these criteria : [substeps] The area should be spacious enough.
A:
D