Which of these illustrates the associative property of multiplication?
A. 4 x (5 x 6) = (4 x 5) x 6
B. 4 x (56) = (45) x 6
C. 6 (9 + 1) = (6 x 9) + (6 x 1)
D. 5 + 0 = 0 + 5