2 3 7 25 121 721 3 (a) (b) (c) (d) (e) Which of the following numbers will come in place of (c)?

The series is × 2 –1, × 3 – 2, × 4 – 3,.....
The given series is in the below pattern ,
First series :-
First term = 2
Second term = First term × 2 - 1
⇒ Second term = 2 × 2 - 1 = 3
Third term = Second term × 3 - 2
⇒ Third term = 3 × 3 - 2 = 7
similarly , we can calculate the all next terms .
Second series :-
First term = 3
Second term = First term × 2 - 1
⇒ Second term = 3 × 2 - 1 = 5
Third term = Second term × 3 - 2
⇒ Third term = 5 × 3 - 2 = 13
Fourth term = Third term × 4 - 3
⇒ Fourth term = 13 × 4 - 3 = 49
Hence , the place value of ( c ) is 49 .