1. 

What should come next in the following letter series?

A B C D E F Z Y X W V U A B C D E Z Y X W V U A B C D Z Y X W V

A. U
B. A
C. B
D. Z
E. None of these

Answer: Option A

Explanation:

Pattern of the series as shown below

ABCDEF/ZYXWVU/ABCDE/ZYXWVU/ABCD/ZYXWVU

Hence, the missing term is U.