A controlled experiment . Group of answer choices Includes at least two groups, one of which does not receive the experimental treatment Is repeated many times to ensure that the results are accurate Proceeds at a slow pace to guarantee that the scientist can carefully observe all reactions and process all experimental data Includes at least two groups, one differing from the other by two or more variables

A controlled experiment includes a control group and at least one experimental group.  Option A). A controlled experiment includes at least two groups, one of which does not receive the experimental treatment.

In a controlled experiment, the researcher wants to identify the effect of one or more variables on something.

Since many different variables might be affecting the results, and most of them are not of interest to the researcher, they must be kept under control. They must remain constant.

There must be at least two groups. One of them must be the control group, and the other one (or other ones) is the experimental group.

During an experiment, the researcher compares the two groups. Both of them are composed of individuals coming from the same population, so they are identical in all aspects except for the independent variables that the researcher changes in the experimental group to observe how they affect the individuals.

Hence, A controlled experiment includes at least two groups, one of which does not receive the experimental treatment.

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A. Includes at least two groups, one of which does not receive the experimental treatment

Explanation:

A control experiment can be defined as an experiment in which a condition assumed to be a probable cause of the effect is being compared to the same situation by the scientist without involving or using the suspected condition.

Also, an experimental group can be defined as a collection of participants that are subjected to the independent variable.

Generally, most scientific experiments usually have a control group so as to avail the scientists (experimentalists) an ability to compare the outcome of their test results. This control group is not given the treatment or influenced by the same independent variable as the experimental group.

Therefore, this is the reason why science completely or totally rejects any hypothesis which is not supported by observations, as well as the results obtained from control experiments.

This ultimately implies that, for any hypothesis to be acceptable in science, it must be supported by observations and the results of control experiments; this give rise to factual informations, theories and by extension solutions to problems.

Hence, a controlled experiment includes at least two groups, one of which does not receive the experimental treatment.

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