If |(r, 2r - 1, 3r - 2), (n/2, n - 1, a), (1/2n(n - 1), (n - 1)2, 1/2(n - 1)(3n + 4))|, then the value of ∑Δr for r ∈ [r=1, n - 1]
(A) depends only on a
(B) depends only on n
(C) depends both on a and n
(D) is independent of both a and n
Answer is (D) is independent of both a and n
