choices.label: A B C D
choices.text: field management:frost and pest clinical trials:adverse reactions weather forecast:satellite cloud image rectify the market:purify the atmosphere
explanation: "increased temperature and water retention" is the result of "plastic film mulch". the purpose of "field management" is to prevent "frosts and pests". "adverse reactions" may be attributed to "clinical trials". the "weather forecast" is based on "satellite cloud images". the purpose of "rectifying the market" is to "purify the atmosphere".
relation: plastic film mulch increased temperature and water retention R3.9
relation: rectify the market purify the atmosphere R3.9