Question

the passage below describes an experiment.
franklin grows herbs in his house. he read that lowering soil ph can help plants grow more quickly. franklin put cuttings of the same herb in six small pots. he watered two of the cuttings with only water, two with water mixed with one tablespoon of vinegar, and the final two with water mixed with two tablespoons of vinegar. after one month, he measured the height of the herbs in each pot.
in this experiment, which were part of an experimental group?
the herbs watered with only water
the herbs watered with water mixed with one tablespoon of vinegar

Explanation:

In an experiment, the experimental group is the one exposed to the independent variable (here, different amounts of vinegar in water to lower soil pH). The group with only water is the control group. The herbs watered with water + one tablespoon vinegar (and also those with two tablespoons) are exposed to the variable, so they are experimental. The option "the herbs watered with water mixed with one tablespoon of vinegar" is part of the experimental group.

Answer:

the herbs watered with water mixed with one tablespoon of vinegar