Given the task definition, example input & output, solve the new input case.
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".
Example: [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.
Output: D
This is a good example. Only option D is about Christmas trees. So, it's the correct option.

New input case for you: [header] How to not let acne get you down [title] See a dermatologist. [step] This is an important first step. In many cases, acne is curable when treated properly. <sep> (A) You can see a dermatologist by asking him or her some important questions about your underlying issues. Be sure to mention this before you start testing your acne with the doctor, as your doctor may want to do additional tests for you. (B) However, it can affect several factors: age: people can develop acne within one decade of age. Due to conditions which develop very suddenly, it is important to see a dermatologist. (C) Dermatologists specialize in treating skin conditions. A recommendation from your doctor will take the guesswork out of trying to treat your acne. (D) But you should always see a dermatologist if acne is something you cannot control, especially if it's a flat, basic problem. It's important to know the severity of acne and what treatment will benefit you and your cause (s) in future life.
Output:
C