Which causal criteria are the most difficult to establish when using cross-sectional designs?

Which of the following is NOT one of the features of George W. Bush's foreign policy following September 11, 2001?

a. Unilateral action b. Right to preemptive war c. Exportation of democracy d. Preference for proxy wars e. Diplomacy

Which did NOT occur during the Grand Apartheid years?

a. Foreign capital and public investment in strategic industries increased, leading to substantial economic modernization and development, and Africans began to move into semiskilled manufacturing jobs. b. Homelands, areas reserved for the exclusive use of Africans, were established. c. The South African government passed laws that allowed detention without trial and made it easier to torture prisoners. d. Restrictions were placed on African, Indian, and Colored enrollment in major universities, and a system of segregated colleges was established. e. The African National Congress was formed.