Final answer:
In programming, an object's lifetime ends when its destructor is called, which is responsible for cleaning up the object before memory is reclaimed.
Step-by-step explanation:
The lifetime of an object in programming ends when its destructor is called. This happens because the destructor's role is to clean up and perform any necessary finalization tasks before the object's memory is reclaimed by the system. It is not when the constructor initializes the object's properties, which is the beginning of the object's life. Neither is the object's lifetime tied to when member functions are invoked, as this is part of its usage during its life. Finally, the declaration of an object within a scope is simply when the object comes into existence, not when its lifetime ends.