Answer: C) As surface area increased, the dissolving time decreased.
Surface area is the area which is exposed for a activity or process to take place. In this case surface of area being judged upon on two cases when students were asked to keep the whole mint in their mouth as such and in other when they were asked to swirl it in the mouth. Swirling inside the mouth will increase the surface area of the mint for dissolution inside the mouth. Therefore, as surface area increased, the dissolution time decreased.