A: 柠檬 AND (气相色谱-质谱 OR GC/MS) B: 柠檬 AND 气相色谱-质谱 OR GC/MS C: (柠檬 AND 气相色谱-质谱) AND (柠檬 AND GC/MS) D: 柠檬 OR 点我阅读全文