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 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.
[A]: D

[Q]: [header] How to care for a cut [title] Wash your hands before treating the cut. [step] You do not want to touch a cut with dirty hands. Before attempting to clean your cut, wash your hands with soap and water. <sep> (A) This will make the cut be less surface-sensitive. [substeps] If you are unable to wash your hands, bring some hand sanitizer with you and wash them thoroughly. (B) Rubbing your hands together can cause irritation, and you may get a serious infection. [title] Scrape the cut with a dentist or surgeon's sharp edge. (C) [substeps] Lather your hands in soap and wash them for about 20 seconds. Make sure to wash under your fingernails and on the backs of your hands. (D) For mild cuts, you may wash your hands with a mild cleanser or special hand sanitizer to hold the bleeding wound and stop it from spreading. Dry the cut quickly with a clean towel and you're finished! [title] Wear gloves.
[A]: C

[Q]: [header] How to learn and understand the chemistry and physiology of enzymes in humans [title] Learn what are enzymes and how they are synthesized in the body. [step] Enzymes are a class of proteins that have special functions in the body of living organisms including human individuals. These enzymes are synthesized in the body by the same mechanism of proteins translational processes that involves the coding of amino acids by codons that are comprised each of three dna bases. <sep> (A) Each codon of three neighboring dna bases codes for one amino acid. This amino acid is in turn transported to the cellular ribosome using special type of rna molecule that is called transfer rna molecule. (B) A molecular environment usually has good biology of their own, the slow enzymes (bmi) are avowable for humans. They are synthesized first in the laboratory, as them. (C) For example, mna is a chemical derived from the core of amino acids. This chemical is then released in everyday life. (D) They are injected into the genital area of the body. [title] Study how our bodies behave in our atmosphere.
[A]:
A