A group of students conducts an experiment to test the amount of sugar that can be dissolved in water at 50°F, 100°F, and 200°F.

Which suggestion will help increase confidence in the result?

A. Michael suggests timing each addition of sugar
B. Ali suggests using her hand to verify the temperature of the water
C. Joel suggests testing salt along with sugar to see if they dissolve at different speeds
D. Zander suggests that each student complete an experiment individually and compare results​