Professor x wants to make sure his study of gifted youngsters will get published, but he’s worried that his findings could have been caused by something other than the independent variable, which was a new teaching method he introduced. he is concerned with the of his experiment.

internal validity

Explanation:

The internal validity measures the degree to which the research is correct. This is done by determining the number of confounding variable.

A confounding variable is the variable that influences both the independent and dependent variable. Only the independent variable should influence the dependent variable.

When the confounding variables found in the research is low the internal validity of the research increases and if the confounding variables found in the research is high the internal validity of the research decreases.

Here, Professor X is worried that a confounding variable is influencing his dependent variable so he is concerned about the internal validity of his experiment.