Hanna hypothesizes that granite is denser than sandstone. How can Hanna test her hypothesis? A. Melt each rock down inside a high-temperature furnace, and then measure the volume of the two liquefied rocks. B. Examine the rocks under a hand lens and determine which rock seems to have the largest particles. C. Weigh each rock to determine which is the heaviest, and thus the densest. D. Measure the mass of the rocks with a balance and the volume of the rocks with water and a graduated cylinder. Then calculate their densities.