第13题: [单项选择]Life on other planets is possible ______. A. when life-evoking conditions exist B. only when their conditions match those of the earth C. when the temperature is neither too hot nor too cold D. when the atmosphere is not too dry 参考答案:A 答案解析:[解析] 事实细节题。由第二句话“life is probably a normal phenomenon wherever the conditions are right,with the add