Correct Answer : All of the above
Explanation :
Destructors are called at the following time :
i) at the end of the program to destroy objects declared in the main() or global scope.
ii) at the end of a function to destroy objects declared at that function scope.
iii) when user by himself tries to delete an object using the delete operator.
iv) at the end of a block to destroy objects declared at that block scope.
