答案:空
A. PWR
B. TXD
C. RXD
D. LOS
A. PASS灯亮绿灯、FAULT灭灯、ACTIVE灯亮黄灯、POWER灯灭灯
B. PASS灯亮绿灯、FAULT亮绿灯、ACTIVE灯亮黄灯、POWER灯灭灯
C. PASS灯亮绿灯、FAULT灭灯、ACTIVE灯亮黄灯、POWER灯亮绿灯
D. PASS灯亮绿灯、FAULT灭灯、ACTIVE灯灭灯、POWER灯灭灯
A. 正确
B. 错误