A controlled experiment is 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 variables constant.
E) is supervised by an experienced scientist.

Question

Quizplus · Accepted Answer

A controlled experiment involves comparing an experimental group to a control group that is kept constant except for the variable being tested. Both groups are tested in parallel to ensure that any observed effects are due to the variable being tested and not to some other factor. This allows for accurate and meaningful conclusions to be drawn from the results of the experiment.

A Controlled Experiment Is One That