Based on the text, why was the sleight-of-hand step an important part… | Verbal SAT Question

In 2005, Swedish researchers studying flawed choice recall devised an experiment in which participants were shown two photos of different faces and asked to select the one they found more attractive. The researchers appeared to give the participants the photo they had chosen, but in fact used sleight of hand to give them the photo of the person they had not chosen. Most participants accepted the swap and, when asked to explain their initial preference, gave justifications for having chosen the face in the photo they were given. Subsequent researchers have replicated this finding with other choices, including jam preferences.

Based on the text, why was the sleight-of-hand step an important part of the experiment?

It allowed the researchers to control for the possibility that some participants found the two faces roughly equally attractive.

It helped the researchers test whether participants would embrace an outcome they thought was consistent with their intention even when it was truly contradictory.

It enabled the researchers to determine whether the thought process involved in selecting which photo had the more attractive face was similar to the thought process involved in selecting a preferred jam.

It allowed the researchers to measure the willingness of participants to change their positions when presented with persuasive counterarguments.