Which list shows all the factor pairs of 28?
A. 1 and 28, 2 and 14, 4 and 7
B. 1 and 28, 2 and 14, 4 and 7, 6 and 8
C. 1 and 28, 2 and 14, 3 and 8, 4 and 7
D. 1 and 28, 2 and 14, 3 and 8