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 know if your dental fillings need replacing [title] Watch for tooth sensitivity. [step] If you have fillings that need replacement, you'll likely feel it first. Paying attention to the physical symptoms of old or decaying fillings can let you know if it's time to have your dentist replace them. <sep> (A) One sign that your fillings may need replacing is if you have tooth sensitivity to temperature, sweets, or pressure. [substeps] Pay attention when you bite into any cold, hot, or sweet foods. (B) Teeth sensitivity occurs when gums become severely stained with white blood. These white discolorations are mainly due to gum disease, but most commonly introduce a white blood cell colony to the side of your mouth. (C) Once your doctor notices an increase in tooth sensitivity, he or she can return you to the dentist. [substeps] Are your teeth hurt or moist? Severe tooth pain, cramping, sensitivity, or tingling are all signs that they need replacement. (D) [substeps] Bad tooth sensitivity is usually not a problem until it gets worse and you start to feel pain. You may experience sensitivity at night and bad teeth at the same time.

A: A
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Q: A man is preparing to run and jump. he <sep> (A) runs very quickly down the track. (B) is doing a stunt, then dismounts to the ground. (C) releases the bar, and lands a few feet away. (D) is blindfolded and jumps full speed into the sand.

A: A
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Q: [header] How to track your diet on fitbit [title] Set up a fitbit account if you don't already have one. [step] Click the " log in " link on the top-right corner of the page and enter your account credentials to sign in. [title] Log in to your fitbit account at www.fitbit.com or in the app. <sep> (A) [step] You'll be asked to provide your personal information (name, phone number, email, etc. ) and password, then you can set up your password. (B) [step] This is where you will keep track of your daily caloric intake. Under your account dashboard, click the " log. (C) [step] You can skip this step if you want to log in from the apple.com myfitbit app on your iphone or ipad. [substeps] If you already have an account on the same iphone or ipad, you won't need to log in. (D) [title] Select, specify, and enter your nutrition data. [step] In the upper right corner of the screen, you'll see a list of all the items you have of equal weight.

A:
B
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