If the coefficients of rth, (r + 1)th and (r + 2)th terms in the binomial expansion of (1 + y)m are in AP, then m and r satisfy the equation
(a) m2 - m(4r - 1) + 4r2 + 2 = 0
(b) m2 - m(4r + 1) + 4r2 - 2 = 0
(c) m2 - m(4r + 1) + 4r2 + 2 = 0
(d) m2 - m(4r - 1) + 4r2 - 2 = 0