What does a postdecrement operator do?

The postdecrement operator specifically reduces the value of the operand by one but does so after the current value has been utilized in the expression where it is present. When the operator is applied (for example, in the expression x--), it will first return the original value of x for that operation and then decrease x by one.

This behavior is crucial in scenarios where you want to utilize the current value before decrementing it for subsequent operations. Understanding this allows programmers to control the order of execution and manage values effectively within loops or complex calculations. Hence, the answer that describes this behavior—subtracting one from the operand after the value is used—captures the functionality of the postdecrement operator accurately.