4.What is true regarding the classifier roles?

a. Two classifier roles cannot have the same base class;

b. A classifier role is a class;

c. A classifier role is an object;

d. A classifier role defines the role that objects can play in interactions;

.e. None of the above.

Please answer the three question and number the answer to avoid confusion. Thanks

5. Given the below sequence diagram, what is the meaning of two '*'s? a. They mean that method m() contains a Vector/Array data structure; b. They mean there are zero or more associations roles involved; c. The '*' is the box means there are zero or more objects of class B involved, and the other one means method m( ) is called many times; d. The above sequence diagram is wrong as '*' appears twice in different contexts; e. None of the above. 6. Given the below UML diagram, which of the following statements are true? a. The stereotype > is incorrectly defined in the object diagram; b. The message passing ' f(a) ' is incorrectly defined in the class diagram; c. The generalization relationship between B and C is incorrectly specified; d. Object ' a ' is passed as a parameter of a message; e. None of the above