在下列措施中，（）对提高视度是无益的。
A、增加照度
B、增大视角
C、提高视看对象与背景之间亮度之比
D、将识别物体时间提高到5min以上
参考答案：D
The dog had such ________ to its master that it would not leave him, even when he
was dead．
A．devotion
B．contribution
C．connection
D．application
羰氨反应
