Question

passage below describes an experiment: image: a bowl of bubbling yeast martha was making bread and noticed that her yeast was creating bubbles when mixed with warm water. martha wondered if her yeast would create more bubbles if she mixed sugar in with the warm water. she added five grams of yeast and 50 milliliters of water to six flasks. she also added two grams of sugar to two of the flasks and four grams of sugar to two other flasks. she attached a balloon to the top of each flask and observed how much each balloon inflated after fifteen minutes. using this experiment, which were part of a control group? the flasks with water and two grams of sugar the flasks with only water

Explanation:

In an experiment, the control group is the one without the variable being tested (sugar here). The flask with only water has no sugar, so it's the control to compare with flasks having sugar. The flask with water and two grams of sugar is an experimental group with sugar.

Answer:

The flask with only water