An experiment that does not effectively control for confounding variables lacks:

Question

Quizplus · Accepted Answer

Internal validity is the degree to which an experiment is free from confounding variables, so an experiment that does not effectively control for these variables lacks internal validity. A refers to whether the experiment measures what it's supposed to measure (which is a different concept), B refers to whether the findings can be generalized to other populations or settings, and C is not a valid term in research methodology.

An Experiment That Does Not Effectively Control for Confounding Variables