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

C. H

In the series X, Y, Z, A, ?, C, D, which letter should fill the gap?

A. B

In a pattern of shapes: Circle, Triangle, Square, Circle, Triangle, ?, Square. What is the missing shape?

B. TRIANGLE

What character should replace the question mark in the sequence: A, B, C, ?, E?

A. D

If the pattern is 1, 2, 4, ?, 16, what number should replace the question mark?

A. 8