1. 

Which single letter can be prefixed to the following words in order to obtain entirely new words?

(Same letter has to be prefixed in all five words)

EAT    OUR    IS    AS    AT
A. S
B. H
C. C
D. B

Answer: Option B

Explanation:

Letter H is prefixed to the following words

H + EAT    ---->  HEAT

H + OUR  ----->  HOUR

H + IS       ----->  HIS

H + AS     ----->   HAS

H + AT     ----->   HAT