Q: 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".
[header] How to make perfect coffee [title] Buy fresh roasted coffee beans. [step] Coffee tastes best when brewed right after the roast. Look for a " roasted on " date on the label, and get the freshest possible. <sep> (A) The optimal beans are ones with roughly the same ph at room temperature. Unground beans are also preferable, because you can grind them raw in order to flavor your coffee. (B) Fresh roasted beans will not taste like " roast off " coffee. If you'd rather have just brewed your own coffee, a " roasted " date is sufficient. (C) Buy no more than two weeks' worth of coffee at once, so it doesn't go stale in your pantry. [substeps] A vacuum-sealed, opaque bag keeps coffee fresher than other packaging. (D) Ripe, robust beans produced while roasted may taste best and taste best even after they've turned brown. [substeps] Select freshly ground coffee beans in a larger pot or mortar.
A:
C