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 clean a popcorn machine [title] Cool the unit. [step] Before cleaning, allow the unit to cool entirely with all components in place. The unit should be allowed to cool on its own. <sep> (A) If it is too hot to allow it to cool completely, the sooner it is washed, the better. [title] Vacuum the tops of the popcorn machine with a corn colander. (B) [substeps] Cooling should take between 30 and 60 minutes. Hot temperatures can cause broken popcorn machine bulbs to burst and splinter. (C) Do not introduce water or other agents to help cool the machine. [substeps] Unplug the machine while allowing it to cool. (D) [title] Inspect the unit for holes or defects. [step] As a food or drug store employee, you may be required to inspect your appliance for leaks, contamination, and other health issues.
Student:
C