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". 
One example is below.
Q: [header] How to create a christmas tree forest [title] Consider the type of tree you want to plant. [step] There are a wide variety of christmas trees and include fir, pine, spruce, cypress, and cedar. These trees thrive in different climates and look different from one another. <sep> (A) It is important to research the tree before setting up your tree to try it out to make sure you can write the tree's growing season so that you can get the most supplies you need. If you're just interested in having a tree stand out, then make sure to check for the following : [substeps] Spruce trees. (B) [substeps] Trees green may be used in a mix of green and evergreen. Greens, such as pintos and olive oil, may be more delicate than these. (C) Where the trees grow together is up to you. [substeps] Spruce trees light up the night for hours in the morning and drown out the morning sunrise between afternoons. (D) Think about where your tree forest will be located and choose a tree that can thrive in that climate. [substeps] Balsam firs are a popular christmas tree species that grow in the northern united states and canada, in hardiness zones 3-5 or states like minnesota, north dakota, and montana.
A: D
Rationale: This is a good example. Only option D is about Christmas trees. So, it's the correct option.
Q: [header] How to make a doll house into a hamster cage [title] Find an unwanted dollhouse. [step] Unless it's particularly grotty, a warm, soapy wash should be sufficient for cleaning the doll house walls, floors and other surfaces. Use a little detergent for something stronger. <sep> (A) This is best done on a warm, sunny day to allow for good drying, or if you're able to leave it in a room which is very, very warm. [substeps] Remove all wallpaper surfaces, carpets and anything else stuck to the dollhouse. (B) [substeps] Ensure the dollhouse is square or rectangular, not a rectangle, as this allows a bigger space. This creates a more nesting space, making it easier to move the doll house. (C) [substeps] For small cages, you'll probably be able to make a cage of a thicker fabric or vinyl material, rather than a plain or doily like material. The material as it dries could damage the hamster, and thus the hamster cage itself. (D) If it smells awful, it is probably not safe to do anything else. [title] Put it away after the wash-out.
A:
A