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". 

Ex Input:
A dog is outside in a large field and runs towards a man holding a yellow frisbee. the man <sep> (A) then throws the frisbee, the dog catches it and begins swimming back and forth in the water. (B) frisbee the dog around the frisbee and the dog chases the frisbee and catches the frisbees. (C) attempts to catch the frisbee but it is deflected by the large dog. (D) then begins walking and throws the frisbee for the dog to catch.

Ex Output:
D


Ex Input:
[header] How to handle a dog's nightmares [title] Decide whether to wake up your dog. [step] When your dog is having a nightmare, your first instinct may be to wake up your dog. However, this isn't always the best idea. <sep> (A) Waking up your dog would disrupt its sleep cycle, causing it to feel confused and possibly lash out at you. It's often better to let a dog continue sleeping through the nightmare. (B) If your dog's nightmares persist and you aren't willing to take the time to monitor your dog, it might be best to enlist the help of a veterinarian. There are several reasons for this : [substeps] When your dog is having a nightmare, your own judgment is impaired. (C) If your dog is claustrophobic or is fear fearful, you will want to be as calm as possible while your dog is having the nightmare. If the fear is mild to moderate, choosing an alternative position or location may not be a good idea. (D) While nightmares are real, traumatic experiences can also happen. [substeps] Nightmares also occur in dogs that have nightmares caused by trauma.

Ex Output:
A


Ex Input:
[header] How to use the paintbrush tool in adobe illustrator [title] Open an adobe illustrator document. [step] You may want to save a new version of an existing document, while you learn to work with the paintbrush tool. Once you have mastered it, you will be ready to change colors, using all its features, on the final document. <sep> (A) [title] Choose an image or image that you want to apply to the brush. [step] If you plan to use the brush tool for effects, choose a larger color or a larger size. (B) [title] Apply about 18 to 30 spots per area. [step] If using this tool, apply just a small amount. (C) [title] Select the layer that you want to change in your layers window, or create a new layer on top of the object to place your brushes on. [step] This will allow you to change the paintbrush work without changing the object itself. (D) [title] Change the margins and the durability of your layer. [step] Use one of the options on the toolbar at the top of the web page to change the margins and durability of your layer.

Ex Output:

C