Which of the following is true about parameter lists in methods?

The correct answer emphasizes that parameter lists in methods specify the data that must be supplied when the method is called. In Java programming, when defining a method, a parameter list is included to declare the types and names of the inputs that the method expects. This is essential because it not only provides clarity regarding what data the method requires to function correctly but also enforces a contract for method usage: any caller of the method must provide the appropriate arguments that match the specified parameter types in order for the method to execute.

For instance, if a method is defined to take two integers as parameters, it will not accept any call that does not provide two integers. This strict adherence enhances type safety, making sure that the right kind of data is being processed within the method.

The options relating to parameters being optional or determining visibility or method names do not accurately describe the fundamental role of parameter lists. While methods can sometimes be defined without parameters, when they are included, they serve the primary function of specifying input requirements.