Question #N1357
The study of the effects of prolonged exposure to artificial light on the human circadian rhythm is a relatively new field, however, the results of these studies have already yielded interesting insights into the potential impact of artificial light on human health.
Which choice best maintains the sentence’s consistent use of verb tense?
A. The study of the effects of prolonged exposure to artificial light on the human circadian rhythm is a relatively new field, however, the results of these studies have already yielded interesting insights into the potential impact of artificial light on human health.
B. The study of the effects of prolonged exposure to artificial light on the human circadian rhythm is a relatively new field, however, the results of these studies have already yielded interesting insights into the potential impact of artificial light on human health.
C. The study of the effects of prolonged exposure to artificial light on the human circadian rhythm is a relatively new field, however, the results of these studies already yielded interesting insights into the potential impact of artificial light on human health.
D. The study of the effects of prolonged exposure to artificial light on the human circadian rhythm is a relatively new field, however, the results of these studies are already yielding interesting insights into the potential impact of artificial light on human health.
Correct Answer is: A
The sentence should maintain a consistent verb tense. The first part of the sentence is in the present tense. Therefore, the second part should also be in the present tense. "Have already yielded" is correct because it maintains the present tense.