What type of future interest cuts short an estate that comes before it?

An executory interest is a specific type of future interest that is designed to cut short a prior estate, effectively terminating it before its natural expiration. This type of interest is held by a third party and becomes possessory upon the occurrence of a specified event. For example, if a grantor conveys property "to A for life, then to B, but if B does not graduate from college, then to C," C holds an executory interest. Should the condition (B not graduating) occur, C's interest activates, cutting short B's estate.

In contrast, other choices describe different forms of future interests. Contingent remainders require a condition to be met before they can become possessory, but they do not cut short a prior estate; rather, they depend on a condition happening after the preceding estate has ended. A reversionary interest occurs when a property interest reverts back to the original grantor after the expiration of a specified estate, but does not cut short the estate while it is still in effect. A vested remainder, on the other hand, is a future interest that is guaranteed to become possessory upon the end of a preceding estate, but it does not possess the ability to cut short that estate; it merely