Question

the passage below describes an experiment.
brenda keeps a vegetable garden in her yard. she germinates her vegetable seeds inside her house before transferring them to her garden. she read that exposing seeds to blue light can cause them to germinate more quickly. brenda set up six grow beds. she left each grow bed in the same location, so they were exposed to the same amount of natural light. in two beds, she planted carrot seeds and exposed them to no additional light. in two other beds, she planted carrot seeds and exposed them to blue light for 12 hours per day. in the final two beds, brenda planted carrot seeds and exposed them to blue light for 24 hours per day. she recorded how long it took for the seeds in each bed to germinate.
in this experiment, the carrot seeds exposed to blue light for 12 hours per day were part of ________.
an experimental group a control group

Explanation:

In an experiment, the control group is the one with no manipulation (here, no additional light), while the experimental group is manipulated (exposed to blue light, like the 12 - hour blue light group). Since this group has the independent variable (blue light exposure) changed, it's an experimental group.

Answer:

an experimental group