In a study of happiness in marriage participants were asked how long they had been married. the time they had been married would be a?

In the study of happiness in marriage, the time participants had been married would be considered an independent variable. This is because it is a factor that could influence the dependent variable, which in this case is the participants' reported happiness in their marriage. By examining the relationship between the length of marriage and happiness, researchers can assess how duration may affect marital satisfaction.