When is a destructor called in C++?

A destructor in C++ is called when an object goes out of scope, which is the reason why this answer is correct. The destructor is a special class member function that cleans up the resources that the object may have acquired during its lifetime. When the scope of the object ends—such as when a function that contains the object returns, or when the object is explicitly deleted—the destructor is invoked automatically. This allows for the proper management of resources, preventing memory leaks and ensuring that any necessary cleanup, such as freeing memory or closing files, is performed.

For example, if you have an object defined in the main function, once the main function completes, the object goes out of scope and its destructor is called, which handles any cleanup necessary for that object.

The other scenarios—before the object is created, after the object is initialized, or when the program starts—do not apply to the invocation of destructors. The destructor can only be called once the object's lifetime has ended, specifically when the object is no longer accessible or referenced in the program.