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 clean the steam iron and its base plate [title] Mix one half cup of water and one half cup of distilled white vinegar. [step] Making a vinegar-based cleaning solution that can disinfect, descale, and deodorize is an economic way to clean inside of your iron. This is also the easiest way to clean parts of the iron that are otherwise unreachable. <sep> (A) [title] Fill the water reservoir of the iron with the cleaning solution, and turn the iron on to heat. [step] Set the iron on its hottest setting. (B) [substeps] You can purchase distilled white vinegar at any pharmacy or department store. If you bought cookware from a grocery store, you can probably find some at your local food bank. (C) [title] Buy or make a small tube cleaner. [step] A tube cleaner is an abrasive cleaning material that will eliminate mold, bacteria, and other germs from inside of your iron. (D) Mix one half cup of vinegar with two pounds of water in a glass dish. For optimal results, follow this with a bit of dish detergent.
A:
A