In Ruby, what is the purpose of the module_function keyword?

A. Writing code that modifies its own structure B. Writing code that writes code C. Writing code that generates other code D. Writing code that optimizes performance

A. Kernel B. MetaModule C. ObjectSpace D. Reflection

A. Intercepting method calls before they are executed B. Defining custom method behaviors based on method names C. Handling undefined method calls D. Providing default implementations for missing methods

A. A class that can have only one method B. A class that is used to define methods for a single object C. A class that can have only one subclass D. None of the above