Identify the missing character in the series 1, 4, 9, ?, 25.

A. 16

In the sequence: M, N, O, ?, Q, R. What letter is missing?

A. P

In the sequence A, B, C, ?, E, F, what character should replace the question mark?

A. D

What character should replace the question mark in the pattern: X, Y, Z, A, B, ?

A. C

In the sequence 2, 4, 8, 16, ?, 64, what is the missing number?

A. 32