A student wants to compare the amounts of CO2 given off by yeast provided
with different amounts of sugar. The student places a balloon over each
container to catch the released CO2. Which observation is a quantitative
observation the student can make to compare the amounts of CO₂ given off?

A. The weight of each filled balloon

B. The temperature of each filled balloon

C. The shape of each filled balloon

D. The relative size of each filled balloon