choices.label: A B C D
choices.text: city:residential area:commercial area satellite:remote sensing:radar candy:fruit candy:sesame candy unit:kilometer:km
explanation: both "physical geography" and "economic geography" are branches of "geography", and "geography" includes "physical geography" and "economic geography". "city" includes "residential area" and "commercial area", but "residential area" and "commercial area" are not branches of "city" "satellite" refers to a celestial body that orbits a planet periodically, "remote sensing" refers to long-distance detection technology, and "radar" is an electronic device that uses electromagnetic waves to detect targets. there is no obvious logical relationship between the three. both "fruit candy" and "sesame candy" belong to "candy", and "candy" includes "fruit candy" and "sesame candy". "kilometer" and "km" mean the same distance.
relation: kilometer km R2.1