对控制系统的最基本要求是（）
A.稳定性
B.快速性
C.准确性
D.可调性
参考答案：A
农业推广沟通的认同过程一般要经历哪些阶段？
I was ______ in my reading, and didn’t at first hear the doorbell ring.
A. immured B. immersed C. busy D. infatuated
