The essential "basic " ingredient in the "creation " of a thunderstorm is "a warm" moist "unstable" atmosphere .
A
basic
B
creation
C
a warm
D
unstable
Correct Answer: a warm
The essential "basic " ingredient in the "creation " of a thunderstorm is "a warm" moist "unstable" atmosphere. 'A' will be omitted before warm because warm modifies uncountable noun 'atmosphere'. So the correct sentence is - The essential basic ingredient in the creation of a thunderstorm is warm moist unstable atmosphere.