Answer:
A. A legal benefit and a legal detriment.
Explanation:
In contract law, consideration refers to the benefit element of value that must be bargained between the two parties.
Consideration always includes a legal benefit because you are going to receive some consideration from the other party, but it also involves a legal detriment because you are also giving away something of value (consideration) in exchange to the other party. E.g. you buy a hamburger (you receive food) but you must pay for it (you exchange money).