In the Ethernet LAN, an algorithm was chosen to dynarnically adapt to the number of stations trying to send. It is called

A． backward learning

B． binary exponential backoff

C． spanning tree

D． CRC

我国海洋产业中，年产量占世界第一位的有（）和（）。

A.海洋石油业和海洋运输业

B.海洋渔业和海洋运输业

C.海洋渔业和海盐业