Which of the following is a characteristic of a good psychological experiment?

A characteristic of a good psychological experiment is the presence of reliability, validity, and control. Reliability refers to the consistency of results across different trials or sets of subjects, ensuring that the findings are repeatable and dependable. Validity encompasses both internal validity, which examines whether the experiment accurately measures what it intends to measure, and external validity, which considers how well the results can be generalized to other contexts or populations.

Control is essential for establishing causation and minimizing confounding variables that could skew the results. By maintaining a controlled environment, researchers can isolate the effects of the independent variable on the dependent variable, thus drawing more accurate conclusions from the data.

The other options do not encapsulate the essential characteristics of a well-constructed psychological experiment. Randomization of subjects alone is not sufficient; it needs to be accompanied by other factors like validity and reliability for an effective experimental design. Ambiguous results can lead to confusion rather than insight, and frequently changing variables can compromise the experiment's integrity and ability to measure outcomes reliably.