题目

March is a Civility month(文明礼貌月) in China. More and more young people are trying to do all they can ________ the elderly.A．helpedB．to helpC．helpD．helps 答案：B解析:略湿地能保持水土、调节气候、净化空气等。这体现了（　　）A.生物影响环境B.生物适应环境C.环境影响生物D.环境适应生物