instruction:
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". 
question:
[header] How to install custom firmware [title] Record the router's model and version number. [step] These numbers are usually located near the manufacturer's logo, underneath or in back of the router. Write down the model and version information for future use. <sep> (A) [substeps] If you are using windows xp (default operating system), the model number can be found in the start menu under " system settings. " skip all the discussion menus, and then go to system preferences. (B) [title] Obtain the router's ip address and default gateway for your computer system. [substeps] Determine the ip address and default gateway for a pc. (C) [substeps] " w " with the green background is the serial number for the model. " p " with the red background means " unhappy operating system. (D) [substeps] It is easy to determine what operating system is running on your router if you don't know the model. Copy the model from the registry to convert it to your operating system.
answer:
B


question:
[header] How to clean a cast iron stove [title] Place an old newspaper on the ground in front of the stove. [step] Do this as a protective measure before you begin scooping ashes out of the stove, as they are liable to drop onto the ground. A newspaper will make cleanup much easier. <sep> (A) [substeps] You might even want to splash some cold water over the newspaper, so the water completely freezes around the newspaper. A drop of lemon juice can also help. (B) [title] Pour about a tablespoon of salt into the newspaper you have saved. [step] Add lemon juice and shake off the salt. (C) [title] Use the newspaper to wipe and scrape any soot out of the cast iron burner. [step] Do this several times until any soot is gone. (D) As you're spreading the newspaper, open the air dampener so that any ash stuck to it will fall into the firebox. [substeps] The air dampener will be a small knob on the front of the cast iron stove, that you should pull outward to open.
answer:
D


question:
[header] How to earn college credits in high school [title] Sign up for ap courses. [step] One way to get college credit in high school is to sign up for ap classes, which may overlap with dual enrollment classes. The advanced placement program (ap) is through the college board. <sep> (A) You will take courses in math, english, and science. The honors classes you receive in high school will help to give you advanced course credit, which can also help you reach your english final. (B) The program allows high school students to take classes with college-level work in a high school setting. At the end of the year, you take a test given by the college board, and if you make a high enough score, you can receive high school credit. (C) Students attending high school will take courses that cover a wide variety of subjects. These courses will help your electives get more advanced and can make it easier to participate in extracurricular activities. (D) This program puts you on the hook for ap credits in large part because it enables you to complete multiple courses in one year. These courses can allow you to stay up-to-date on college credits.
answer:

B