The evidence supports the conclusion that the experiment was ______ controlled.

• A. safely
• B. rigidly
• C. loosely
• D. poorly

Answer: (D)

Control of variables in an experiment is about keeping other factors constant so that any observed effect can be truly attributed to the factor being tested. If the evidence indicates the experiment was poorly controlled, it means important variables weren’t adequately kept constant, procedures weren’t standardized, or participants weren’t assigned in a way that prevents bias. That kind of deficiency points to weak reliability and validity because uncontrolled factors could have influenced the results.

Other descriptors would change the sense. Safely is about safety, not methodological control. Rigidly would suggest an unusually high level of control that isn’t implied by the evidence. Loosely would imply only weak control, but the data described by “poorly” conveys a clearer, stronger shortcoming in controlling variables. So, poorly controlled best fits the idea that the experimental conditions weren’t adequately managed.