Answer:
A. They were part of the control group
Explanation:
In a scientific experiment, the CONTROL GROUP as opposed to the experimental group is the group that does not receive the experimental treatment. This acts as a standard for comparison.
In this question, the EXPERIMENTAL VACCINE is the experimental treatment or independent variable that was added. The five animal test subjects that was injected with this vaccine are called the EXPERIMENTAL GROUP while the other five test subjects that were rather injected with a PLACEBO are called CONTROL GROUPS.
The anther and filament, the anther produces pollen. They are the parts of the male reproductive organ in a flower.
<h3>What are the male parts of the flowers?</h3>
The flower can be considered as the reproductive structure of flowering plants.
The anther and filaments represent the male structures of a flower, which may also contain female structures.
The stamen can be considered as the male reproductive organ because this structure is responsible for producing pollen which contains germinal cells in a flower.
Learn more about flower parts here:
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