The soldiers who were struck by the gas attack in this passage experienced

A. eye irritation.

B. skin blisters.

C. sudden death.

D. sleepiness.

Eye irritation.

Explanation:

There were several types of gases used during WWI (that's what I'm assuming this question is about) but all of them caused severe eye irritation, which would lead soldiers to sometimes take off there gas masks completely and expose the to the gas completely. That's why 85% of deaths in the war were though to be gas related. But instant death could be the other answer just because one of the gasses was particularly lethal and caused many deaths in the war.

c. sudden death.