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 get oil out of hair [title] Shampoo your hair several times. [step] Use your regular shampoo to wash your hair in the shower. Really work the shampoo into your scalp using your fingers and rinse it out thoroughly with lukewarm water. <sep> (A) Rinse your hair as soon as possible after it is done, as prolonged washing can hurt the scalp. [title] Dry your hair as soon as possible. (B) Have a good conditioner available on hand for long-term use. [substeps] Because oil can build up if you're not getting it regular, don't rinse it out very often, as this may clog or unbalance the hair follicles. (C) Repeat the process one or two more times, as needed. [substeps] After you finish shampooing, add some conditioner to your hair and let it sit for 5 minutes before rinsing out. (D) [substeps] You can use a hairdryer, a microfiber cloth, or a shower cap to gently detangle your hair to avoid spreading the oil or holding your hair in. [title] Squeeze a dime-sized amount of shampoo from a bottle.
C

[header] How to change trackpad settings on macbook pro [title] Find the system preferences. [step] Starting from your main desktop screen there are two ways to find the system preferences where the mouse and touchpad settings will be located : [title] Bring your cursor to the bottom screen and find the system preferences application. [step] The icon looks like a box with three gears inside it. <sep> (A) Open that to find all your system preferences. [substeps] Alternatively, you can use the spotlight feature. (B) On macbook pro this icon resembles a round blue square with a horizontal green dot on it. On other applications this icon is actually a box with a gear, and is small in appearance. (C) It can be located on the taskbar or in the upper left-hand corner of the window. [title] Let the system preferences application perform its work. (D) [title] Click the customize key in the dialog box. [title] Follow the on-screen instructions to change the customization function.
A

[header] How to make silver nitrate [title] Wear proper protective equipment. [step] The chemicals necessary for this process are highly toxic and can lead to injury if not handled properly. Eye protection, gloves, and a lab coat are necessary to remain safe. <sep> (A) You should also wear long, loose sleeves or long pants to protect yourself from these hazardous chemicals. Be sure you wear good quality work clothes. (B) Long pants and closed-toe shoes, preferably without mesh, should be worn to protect against floor spills. [substeps] Eye protection should completely cover your eyes and the sides of your eyes to protect from splashes. (C) Your lab coat can protect your skin and prevent pollution while working. Ask your local hazardous waste management company to provide you with an appropriate safety gear. (D) Wear full, protective safety gear as well to get the job done effectively. [title] Choose a location for your lab lab.
B