question: airplane:sky
choices.label: A B C D
choices.text: trees:leaves current:wire clocks:hands history:historical records
explanation: the "airplane" flies in the "sky". "leaves" are part of "trees". "leaves" cannot flow in "trees" . "currents" flow in "wires". the "hand" is an integral part of the "clock", and the "hand" cannot flow in the "clock". "historical records" record "history", and "historical records" cannot flow in "history".
relation: airplane sky R3.5