1, 9, 25, 49, 81, ?

The answer is 121.

The sequence is a list of squares of the first 10 natural numbers. The square of a number is the product of that number and itself. For example, the square of 3 is 3 x 3 = 9.

The next number in the sequence is the square of 11, which is 121.

A. 100 is not a square of any natural number.
B. 112 is not a square of any natural number.
C. 121 is the square of 11.
D. 144 is the square of 12.