Select the number from among the given options that can replace the question mark (?) in the following series.
3,4,7,12,19,28,?

Correct option is A

Given series: 3, 4, 7, 12, 19, 28,

Logic: +1, +3, +5, +7….

4 - 3 = 1

7 - 4 = 3

12 - 7 = 5

19 - 12 = 7

28 - 19 = 9

The differences between consecutive numbers are increasing by 2: 1, 3, 5, 7, 9.

Following this pattern, the next difference should be 11 (9 + 2).

So, the next number in the series is:

28 + 11 = 39

The correct answer is (a) 39.