Identify the missing letter in the series: Z, X, V, T, ?

D. U

Find the missing letter in the series: M, N, O, P, ?

A. Q

What is the next letter in the series: A, E, I, M, ?

A. O

Complete the series: x, u, r, o, ?

A. L

What letter comes next in the series: A, E, I, M, ?

A. O