Determine whether following statements are correct, if correct, write out the output.
int a = 4;
(A) a += (a++); (B) a += (++a); (C) (a++) += a; (D) (++a) += (a++);
The output of A is 9
The output of B is 10
C is not correct, error C2106: '+=' : left operand must be l-value
The output of D is 11