Jatinder wrote:Modern inventions such as the pneumatic drill
may seem to have improved the work conditions
of manual laborers, but in fact, have increased
the incidence of health hazards such as silicosis
because it has aggravated the dust hazard
involved in excavation and demolition.

(A) have increased the incidence of health
hazards such as silicosis because it has
aggravated the dust hazard


it singular pronoun refers to the plural antecedent "Modern inventions"

(B) has increased the incidence of health
hazards such as silicosis because it has
aggravated the dust hazard


SV..Plural subject modern inventions to singular verb has

(C) have increased the incidence of health
hazards such as silicosis because they
have aggravated the dust hazard


Correct agreement and pronoun mapped correctly to antecendent

(D) increased the incidence of health hazards
such as silicosis because they aggravated
the dust hazard

Incorrect tense...Tense should be present perfect...

(E) increased the incidence of health hazards
such as silicosis because of aggravating
the dust hazard

Incorrect tense...Tense should be present perfect...


OA affter discussion.
(Can we please follow the format as i followed in the subject - Topic_source of the question)