A factorial, represented as 
 (where
 (where 
 is an integer), is equal to the product of itself and all integers less than it until you get to one. Represented mathematically, we could say:
 is an integer), is equal to the product of itself and all integers less than it until you get to one. Represented mathematically, we could say:

When we use the formula, we can find 4!, as shown below:



4! is equal to 24, or the last answer choice.