When DNA ladder's rungs are the same width, why do A-T and G-C form complementary base pairs according to Chargaff's rule

AThe larger C pairs with the smaller A, and the larger G pairs with the smaller T.

BThe larger A pairs with the smaller G, and the larger T pairs with the smaller C.

CThe larger A pairs with the smaller T, and the larger G pairs with the smaller C.

DThe larger T pairs with the smaller A, and the larger C pairs with the smaller G.