When data are collected on the entire population, this type of study is referred to as

Which of the following is true of the method of agreement used in comparative politics?

A. It looks at attributes that are absent when similar outcomes occur. B. It fails to rule out the possibility that other attributes may also cause the concerned outcomes. C. It serves as the strongest method for making causal inferences in comparative politics. D. It fails to study real-life events and confines itself to hypothetical situations. E. It focuses on similar attributes that lead to the different outcomes.

All of the following are considered to be nontariff barriers except

a. voluntary export restraints. b. health and environmental regulations. c. quotas. d. taxes on imports.