A. Some animals and plants depend on each other for existence. B. Some animals and plants develop their relationship easily. C. Some plants depend on each other for food. D. Some animals live better together. 参考答案:A 答案解析:[解析]从文章第二段最后两句:In their skins...needs to breathe.If the plants are killed...the corals will die.说明了动
第28题: [单项选择]患者,女,50岁,左下8765右下5678缺失,余牙正常,口底至舌侧牙龈距离为10mm,设计铸造可摘局部义齿修复。左下4右下4设计RPI卡环组。如果用RPA卡环组代替RPI卡环组,则圆环形卡环臂的坚硬部分应位于基牙的() A. 颊侧近中,观测线上方的非倒凹区 B. 颊侧近中,观测线下方的非倒凹区 C. 颊侧远中,观测线上方的非倒凹区 D. 颊侧远中,观测线上缘 E. 颊侧远中,观测线下方的倒凹区 参考答案:D