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.