The phrase "other things equal" means that when analyzing the relationship between two variables, other relevant factors are assumed to be constant. This allows for a clearer examination of how one variable influences another without interference from additional variables. It is particularly important in fields such as economics and social sciences. ;
The phrase "other things equal" means that when analyzing the relationship between two variables, all other relevant factors are assumed to remain constant. This assumption, vital in economics and social sciences, allows for a clearer examination of specific relationships. Therefore, the correct answer is D: a number of relevant variables are assumed to be constant.
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