what happens if destructor is not present?

Answer 1

nothing will happen :)
destructors are optional :)
they are not required to be present in your code.

Answer 2

not thing

Answer 3

destructors are optional... you can use them or not use them.... just in case: they are used to do stuff before deleting an object... like writing by console "destruction >:D!!"

Answer 4

destructor are not necessarily added.... a program can run successfully without using a destructor.

Answer 5

Our world will be safe

Answer 6

memory is not freed

Answer 7

the compiler will not let you create a class