For nonnegative integers s and r, let s! if r s, r!(s-r)! 0 if r > s. For positive integers m and n, let g(m, n)-f(m,n,p) n+p p=0 where for any nonnegative integer p, f(m.n.p) = (m)(n+) (P+) i=0 Then which of the following statements is/are TRUE? (A) g(m, n) = g(n, m) for all positive integers m, n (B) g(m, n+1) = g(m + 1, n) for all positive integers m, n (C) g(2m, 2n) = 2g(m, n) for all positive integers m, n g(2m, 2n) = (g(m,n)) for all positive integers m, n (D)