On the basis of which idea did Nazis call people superior and inferior?

Correct answer: Racial theory

The direct answer is A: racial theory. The Nazis divided human beings into supposed races and falsely claimed that some groups were biologically superior while others were inferior. This was not a valid scientific conclusion; it was a racist ideology used to justify unequal rights, exclusion, persecution, and mass murder. The reasoning is simple: Nazi policies classified people by ancestry, treated the so-called Aryan or Germanic group as superior, and targeted Jews, Roma, disabled people, Slavic peoples, and other groups. Option A is correct because racial theory was the central false idea behind these rankings. Option B, climate theory, studies how climate varies and does not explain Nazi racial classification. Option C, sports theory, concerns games and physical activity, not human worth or citizenship. Option D, trade theory, concerns buying, selling, and economic exchange, not biological or social hierarchy. Students should also avoid repeating Nazi claims as facts: they were propaganda and pseudo-science. Memory cue: Nazi superiority claims were based on racism, not real science.