What is defined as an experimental trial added to ensure proper execution of an experiment?

The term that describes an experimental trial added to ensure proper execution of an experiment is the control. A control is essential in scientific experiments because it serves as a baseline or standard for comparison against the experimental group. By maintaining conditions that are not influenced by the independent variable, researchers can determine the actual effects of their experimental manipulations.

Controls help ensure that any changes observed in the dependent variable are a direct result of the manipulation of the independent variable and not due to external factors or random variations. This allows for more reliable and valid results, as it isolates the variable being tested.

In contrast, the independent variable refers to the factor that is manipulated by the experimenter, while the dependent variable is the outcome that is measured to assess the effect of the manipulation. The hypothesis, on the other hand, is a proposed explanation or prediction that is testable within the experiment, but does not constitute an experimental trial in itself. Thus, the role of the control in ensuring proper execution of an experiment is crucial for scientific rigor and accuracy.