题目

If you live in certain parts of the world, you will see something magical happen each fall. It is the changing of the color of the leaves on many different trees. Each year deciduous (落叶的) trees go through a process in which their green leaves become bright yellow, gold, orange and red before turning brown and falling onto the ground.Photosynthesis (光合作用) is the process for trees to make their food taking energy from the sun, water from the ground, and carbon dioxide from the air, they make sugar to “eat” so they can grow into strong, healthy trees. The leaves of a tree are w水是生命之源。下列解决我国水资源不足的途径中，我们中学生能直接积极参与的是A.跨流域调水B.节约用水，防治水污染C.修建水库D.淡化海水