Given:



public class MarkList {
int num;
public static void graceMarks(MarkList obj4) {
obj4.num += 10;
}
public static void main(String[] args) {
MarkList obj1 = new MarkList();
MarkList obj2 = obj1;
MarkList obj3 = null;
obj2.num = 60;
graceMarks(obj2);
}
}

How many objects are created in the memory runtime?

A. 1
B. 2
C. 3
D. 4

題解

僅在第10行有用new運算子實體化出一個MarkList物件。