Yeast Fermentation Requires Sugar for CO2 Production Steps: - Identify gas source: Balloons inflate from CO2 gas produced by yeast fermenting sugar into CO2 and ethanol. - Analyze Flask 1: Contains water, yeast, and sugar, enabling fermentation and maximum CO2 output. - Analyze Flask 2: Contains water and yeast but no sugar, preventing fermentation; yeast may produce trace CO2 from reserves, causing slight inflation. - Analyze Flask 3: Contains only water, with no yeast or sugar, resulting in no gas production or inflation. - Order by inflation: Flask 1 most, Flask 2 slightly less, Flask 3 least. Why B is correct: - B (1→2→3) matches the decreasing CO2 production, as fermentation (anaerobic respiration by yeast) requires both yeast and a sugar substrate per basic biology principles. Why the others are wrong: - A: Wrongly ranks Flask 3 above 2; water alone produces no gas, unlike yeast's minimal activity. - C: Erroneously places Flask 3 as most inflated, ignoring lack of any reactants for gas. - D: Reverses the order, contradicting that sugar enables the most gas via fermentation. Final answer: …