Select the number from the given options that can replace the question mark (?) in the given series.
7, 14, 21, 28, ?

Given:
7,14,21,28,?
Logic: In this given series the difference of two consecutive numbers is +7.

14 - 7 = 7 

21 - 14 = 7 

28 - 21 = 7 

Similarly:

? - 28 = 7 

? = 28 + 7

? = 35

Alternate method

The pattern followed here is,
7___14___21___28___35
   +7       +7      +7     +7
= 35

Thus, correct option is (d).