Question

Which experimental design decision would most likely produce invalid and unreliable results? having more than one controlled variable having only one control group having more than one independent variable having only one experimental group

Answer 1

An experimental design decision is one which has to clear and precise.

The inference or the decision is made by the observations made during the experiment.

The experiment can have only one inference based on the independent variable.

The independent variable determines the value that needs to be calculated or the decision that needs to be made from the observations of the experiment.

Hence, experimental design decision would most likely produce invalid and unreliable results when having more than one independent variable.

The answer is having more than one independent variable.