The Following Function Should Swap the Values Contained in Two

The following function should swap the values contained in two integer variables, num1 and num2. What, if anything, is wrong with this function?
Void swap(int num1, int num2)
{
Int temp = num2;
Num2 = num1;
Num1 = temp;
}

A) You must first initalize temp to 0 before using it.
B) The variable temp should first be set to num1, not num2.
C) The swap function must use reference parameters.
D) The last line should be temp = num1.
E) Nothing is wrong with this function.