Teacher: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".
Teacher: Now, understand the problem? Solve this instance: [header] How to winterize a vacant home [title] Turn off the water at the exterior. [step] Make sure that the water supply is turned off completely at the main supply point. If the furnace should fail on a very cold day, water in a pipe could freeze and burst the pipe. <sep> (A) [substeps] If the home is a bit more sophisticated, you may use a valve to shut off the water supply. If the water is cold enough, this may make the problem easier to fix. (B) [substeps] You can turn off the power by forcing the power switch to into a shut off switch, changing the switch every 40 minutes, or by removing the lights and light fixtures. Make sure to read the manufacturer's manual before beginning your winterizing routine. (C) [title] Open all faucets and drain all waterlines. [step] If you live in an area where freezing pipes can be a problem, drain the toilets, the water heater (turn off the gas or electric supply first) and the expansion tank. (D) Keeping pipes running away from the house is the safest way to winterize a vacant home, as it is not conforming to another system. If hot water leaks through the exterior wall after you winterize, the home will have more gas for the winterization process.
Student:
C