If Matrix A is of order X*Y and Matrix B is of order M*N, then what is the order of the Matrix A*B given that Y=M?

If Matrix A is of order X*Y and Matrix B is of order M*N, then what is

1.	If Matrix A is of order XY and Matrix B is of order MN, then what is the order of the Matrix A*B given that Y=M?
A.	Y*N
B.	X*M
C.	X*N
D.	Y*M
Answer» D. Y*M