Question

A controlled experiment is the one that

a. proceeds slowly enough that a scientist can make careful records of the results.

b. tests experimental and control groups in parallel.

c. is repeated many times to make sure the results are accurate.

d. keeps all the variables constant.

Short answer

1. The statement “proceeds slowly enough that a scientist can make careful records of the results” is false.
2. The statement “tests experimental and control groups in parallel” is true.
3. The statement “is repeated many times to make sure the results are accurate” is false.
4. The statement “keeps all the variables constant” is false.

Step-by-step solution

Explanation of option “a”

The controlled experiment is the experiment that does not proceed slower in manner. All the experiments consume a definite time-space.

Thus, it is a standard description of the experiment in general.

Therefore, the given statement is false.

Explanation of option “b”

The experimental phenomena in which the variable or test factor compares with the control group are the controlled experiments. All the experimental procedures proceed for the control group in parallel.

These control groups are the factors that are kept constant throughout the experiment and are used to cross-verify the results.

Thus, the control group is the essential factor that is constant to carry out the controlled experiment

Therefore, the given statement is true.

Explanation of option “c”

All the experimental procedures proceed to ensure accurate results. The accuracy of experiments is confirmed by experimenting in a repeated manner. This repetition of an experiment is known as trails.

Thus, the controlled experiments are not the method to carry more investigations to arrive at accurate results.

Therefore, the given statement is false.

Explanation of option “d”

The experiments proceed to analyze the variables present in the investigation. There is no point in keeping all the variables constant. The experiment’s final results will be unpredictable if all the variables are kept constant.

Thus, the control group is the only constant factor to compare with the experiment results.

Therefore, the given statement is false.