What must be true for a method to return a value?

For a method to return a value, it must include a return statement. The return statement is critical because it specifies the value that the method will provide back to the caller once it completes its execution. Without this statement, either the method would not return any value, or if it does have a specified return type, it could lead to a compilation error.

In Java, when a method is defined to return a specific type, such as an integer or a string, the method must include a return statement that returns a value of that type; otherwise, the Java compiler will flag an error. This requirement ensures that the flow of data is explicit and controlled, allowing for proper interaction between different parts of a program.

The other options present different scenarios that do not align with the fundamental requirement for returning values from methods. For instance, a method defined with a return type cannot be void, as void signifies that no value will be returned. A method can have parameters and still return a value, and the access modifier does not affect the ability of a method to return a value; it only controls the visibility of the method within the program.