题目

There were two roads ______ to the station.A lead            B. led               C. leading             D. to lead 答案：C2、自然界中存在氧循环和碳循环，其中能降低大气中二氧化碳的是（　　）A、汽车尾气的排放B、人和动物的呼吸C、植物的光合作用D、化石燃料的燃烧