Select the number from among the given options that can replace the question mark (?) in the following series.
2, 6, 12, 20, 30, 42, ?

Correct option is B

Let's analyze the given series:
2, 6, 12, 20, 30, 42, ?
First, find the differences between consecutive numbers:
6−2=4
12−6=6
20−12=8
30−20=10
42−30=12
The differences form the series:
4, 6, 8, 10, 12
This series has a difference of +2 between consecutive numbers. Hence, the next difference should be:
12 + 2 = 14
Adding this difference to the last number in the original series:
42+14=56
The answer is:
B) 56
Alternative method;

Thus, correct option is (b).56