What role does a destructor play in programming?

A destructor is a specialized function that is called automatically when an object is about to be destroyed or deallocated. Its primary role is to perform necessary cleanup tasks, such as releasing resources that the object may have acquired during its lifetime, like memory, file handles, or network connections. This ensures that all resources are properly freed and that the program does not run into issues like memory leaks or resource contention when an object is no longer needed.

The cleanup tasks performed by a destructor are crucial for maintaining the health of the program and managing resource utilization effectively. Without a destructor, program stability may be compromised, leading to various issues when objects are removed from memory.

The other options do not accurately describe the function of a destructor. Initializing new objects is the role of a constructor, encapsulating a set of related functions pertains to the concept of classes and methods, and defining the visibility of variables relates to access modifiers. Therefore, the correct identification of a destructor's role as one that allows for cleanup tasks when an object is destroyed highlights its critical importance in resource management within the context of object-oriented programming.