Identify the missing letter in the series: a, e, i, o, ?

A. U

Complete the series: a, e, i, o, ?

A. U

A, E, I, M, ?

B. O

Find the missing number in the series: 5, 11, 23, 47, ?, 191

A. 95

Identify the missing letters in the series: a, d, g, j, ?

A. M