A function must return zero or more values to its calling environment, whereas a procedure returns a value to the calling environment.

The statement in the question is false. In PL/SQL, a function MUST return exactly one value to its calling environment, while a procedure returns zero or more values (through OUT parameters). The question claims the opposite - that functions return zero or more and procedures return one value. Therefore, the correct answer is False (option B). Functions are designed to compute and return a single value, whereas procedures are designed to perform actions and can optionally return values through output parameters.