Consider the following code segment.
num += num;
num *= num;
Assume that num has been previously declared and initialized to contain an integer value. Which of the following best describes the behavior of the code segment?
A: The value of num is two times its original value.
B:The value of num is the square its original value.
C:The value of num is two times the square of its original value.
D:The value of num is the square of twice its original value.
E:It cannot be determined without knowing the initial value of num.