If the pattern is X, Y, Z, A, B, what is the next letter?

A. C

In the sequence 5, 10, 20, 40, what is the next number?

C. 80

What is the 10th letter of the English alphabet?

A. J

In the series A, B, C, D, E, F, G, H, I, J, how many letters are there before the letter E?

A. 4

What is the 15th letter of the English alphabet?

A. O