When a person suddenly loses consciousness, a bystander is not expect
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10 May 2021, 08:18
Got the answers from 2nd blank.
"effects" is the main clue here. A person attempts something only to counter the effects of something. Hence, counter is the correct choice here.
Now if someone counters the effect, then definitely he would diagnose (to identify the nature of something) the problem, not detect (discover) the problem. Since, the sentence is related to science, the context would make more sense from diagnose. Cure is out of scope.
Hence, C and E.