2,2,5, 13,28,?
Answer: D
The pattern is + 0, + 3, + 8, + 15, ..... i.e. + (l2 - 1), + (22 - 1), + (32 - 1), + (42 - 1), ..... So, missing term = 28 + (52 - 1) = 28 + 24 = 52.