Assume there is no operator overloading implemented, which of the following operation is legal for struct$/$class variables?

Question $2$ options:

x$++$; $//$ x is a struct$/$class variable.

cout $<<$ x; $//$ x is a struct$/$class variable.

x $=$ y; $//$ x and y are $2$ variables of the same struct$/$class$.$

cin $>>$ x; $//$ x is a struct$/$class variable.