Which type of validity is being referred to in the following questions? a

Which type of validity is being referred to in the following questions?

a. Is the statistical test appropriate to ensure a correct conclusion about a causal relationship between the independent variable and the dependent variable?

b. Did variable A cause variable B or is the observed relationship due to some uncontrolled factor(s)?

c. If it is a causal relationship, what constructs are involved in the cause–effect relationship?

d. Can we generalize this causal relationship to other persons, settings, and times?