Detailed Instructions: 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".
Problem:[header] How to dye your hair with coffee [title] Brew some coffee. [step] Brew about 1-2 cups (240-470 ml) of organic coffee. The coffee should be organic, because non-organic coffees usually have added chemicals and preservatives. <sep> (A) For best results, make your own coffee by just boiling water for at least 30 minutes before you dye. [substeps] It's important to pour the brewed coffee into a shaker and bring to a boil. (B) [title] Reserve the coffee, if you don't already. [step] Coffee typically comes with an anti-aging coffee stain, which means it defroshes much faster in the summer than it does in the winter. (C) It is important to serve the coffee as soon as possible to ensure that it takes at least 24 hours to brew. If the coffee is sitting in your refrigerator, turn it cold to speed up the process. (D) Be sure to use a dark roast coffee or espresso. This will help make sure your hair will darken with the coffee.
Solution:
D