In the series: 1, 4, 9, ?, 25, what number should replace the question mark?

A. 16

Identify the missing letter in the pattern: M, N, O, ?, Q.

A. P

What is the missing number in the sequence: 2, 5, 10, ?, 26?

C. 21

Find the missing character in the series: X, Y, ?, A, B.

A. Z