GMAT Sentence Correction (SC) | Re: The use of lie detectors is based on the assumption that

in a sentence
in an individual is prepositional pharse
modifier must modify the noun or pronoun or something near it.

Here subject emotional reactions must have plural verb.
create is correct.

if we see options only option A and D have create.

But option D is wrong because to create is inifinitive it is not a verb.

so option A is correct.

In option E , who is a realtive pronoun modifies individual , it destorts meaning. it says that individual itself create physiological responses.
Actually,
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