question: oxygen:ozone
choices.label: A B C D
choices.text: salt:sodium chloride sulfuric acid:sulfur graphite:diamond lime water:calcium hydroxide
explanation: both "oxygen" and "ozone" are made up of only the element oxygen. "sodium chloride" is the main component of "salt", and "salt" and "sodium chloride" are not composed of only one element. "sulfur" is composed of the sulfur element, but the chemical formula of "sulfuric acid" is composed of three elements: hydrogen, sulfur and oxygen. "sulfuric acid" and "sulfur" are not composed of only one element. both "graphite" and "diamond" are composed of carbon only. the aqueous solution of "calcium hydroxide" is "lime water", "calcium hydroxide" is a part of "lime water", and "lime water" and "calcium hydroxide" are not composed of only one element.
relation: oxygen ozone R3.10
relation: sodium chloride salt R2.3
relation: graphite diamond R3.10
relation: lime water calcium hydroxide R2.3