第11题: [单项选择]In a "primary succession", what makes it possible for mosses to take root A. The type of rock. B. The amount of sunlight. C. The amount of moisture. D. The effect of lichens. 参考答案:D 答案解析:[解析]事实细节题。第三段的第二句话中,作者提到了首先能在岩石上生存的植物是lichen(地衣),然后地衣的影响才使moss(苔藓)的生长成为可能,故选D)。A)项“石头的类型”是针对于第二段中“Fi