Click the Exhibit button. When designing a DWDM system with multiple amplified spans, a pre-amp is needed at Site B to ().<br /> <img src="https://nimg.ppkao.com/2018-08/gelingxia/2018080113561481444.jpg?sign=a2a189de40517846dbdacb59fad514c2&t=62d09368" /><br />
A、 offset the OADM loss at site B
B、 overcome the high multiplexer loss at site A
C、 amplify signal levels after the high loss through Fiber Span 1
D、 adjust add channels at site B to be at the same level as the passthrough channels
E、 ensure that the per channel power is higher than the minimum needed for the post-amp at Site B