Ok the correct answer is A, explanations in -line....
Some expert handwriting analysts can perform what look like psychic feats; by scrutinizing not only the size and shape of the letters but also the pressure exerted on the paper, these analysts can distinguish between forged and legitimate handwriting samples identical to the untrained eye.
between forged and legitimate handwriting samples - CORRECT
between forged and legitimate handwriting samples that were - - we need simple present here "that were" should be "that are"
among forged and legitimate handwriting samples that are - Among is WRONG... cant use among for 2 quantities...
among forged and legitimate handwriting samples though they are - cant use among for 2 quantities...
forged and legitimate handwriting samples - Without the word "between", there can be no comparison between the forged and legitimate samples
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