You will be given a definition of a task first, then some input of the task.
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 bone broth [title] Use cartilaginous bones. [substeps] Collagen, which is found in cartilaginous bones like the joints, neck, head and feet, renders gelatin. For chicken broth, use 2 chicken feet in addition to the other bones. <sep> (A) For beef broth, use sections of a calf's foot. You can find these things at your local butcher, or you can ask your local farmer to bring you some. (B) Press the bones firmly into the broth. You can find them in your local butcher or grocery store. (C) [title] Use equal proportions of cooking salt and butter. [step] The ratio of salt to cooking oil in the broth makes it easier to whisk. (D) This will render it a basic broth rather than a whole, so it is obvious that the bones of the chicken face are a unit instead of a whole thing. Cloth can be used also, but you wouldn't want to overcook your broth for easier pureing.
Output:
A