[A] addition [B] brief [C] general [D] fact

A.serial;

B.async;

C.bri;

D.console;

E.aux

A.2B+D

B.30B+D

C.同轴电缆

D.普通电话线

A.2B+D

B.30B+D

C.同轴电缆

D.普通电话线

A.32

B.64

C.128

D.56

A.ISUP

B.TUP

C.PRI

D.BRI

A.The BRI comprises a Silk Road Economic Belt and a 21st century Maritime Silk Road.

B.The BRI composes a Silk Road Economic Belt and a 21st century Maritime Silk Road.

C.The BRI comprises a Silk Road Economic Belt and a 21st century Silk Road.

A.TCP

B.UDP

C.ISUP，TUP

D.PRI，BRI

A.2B+D

B.23B+D

C.30B+D

D.43B+D

A.1B+2D

B.2B+D

C.30B+D

D.23B+D

A.54Kbps

B.64Kbps

C.36Kbps

D.16K