Answer:
B. A condition precedent
Step-by-step explanation:
A condition precedent refers to an event i.e. needed prior something else would arise. It is an event that must arrise until its non-occurence would be excused prior performing under a contract treated to be due i.e. prior any type of contractual duty would be existed
So according to the given situation, it is a condition precedent
Therefore the option b is correct