The gas inside each balloon takes up the same amount of space. The difference in the mass of the balloons is only a few grams at most. The balloon resting on the table is filled with air. The floating balloon is filled with helium gas. Why might the helium balloon float while the other rests on the table? A. Helium has less mass in the same amount of space than air does, so the helium balloon sinks in air.

B. Helium has less mass in the same amount of space than air does, so the helium balloon floats in air.

C. Air has less mass in the same amount of space than does helium, so the helium balloon sinks in air.

D. Air has less mass in the same amount of space than helium does, so the helium balloon floats in air.