What character should be inserted in the sequence X, Y, ?, A, B, C?

A. Z

In a sequence of letters: A, C, E, G, ?, K. What is the missing letter?

B. H

In a pattern of letters: X, Y, ?, Z, A. What is the missing letter?

A. W

If the pattern is 1, 4, 9, ?, 25, 36, what number should replace the question mark?

A. 16

What is the missing character in the sequence: M, N, O, ?, Q, R?

A. P