question: uncle:nephew
choices.label: A B C D
choices.text: grandfather:father uncle:aunt father-in-law:son-in-law wife:son
explanation: "uncle" and "nephew" are mutual appellations "grandfather" is the "father" of "father", and "grandfather" and "father" do not constitute mutual appellations. "uncle" is the husband of "aunt", and "uncle" and "aunt" do not constitute mutual appellations. "father-in-law" and "son-in-law" are mutual appellations "wife" is a spouse, "son" is a child, "wife" and "son" do not constitute mutual appellations.
relation: uncle nephew R3.10