以下哪个协议提供128-kbit/s的ISDN连接（）

A.带宽分配协议

B.点对点隧道传输协议

C.多链路PPP

D.多播

A.boolean b; switch (b) { case...}

B.int i; switch (i) { case...}

C.String s; switch (s) { case...}

D.char c; switch (c) { case...}

A.index

B.insert

C.split

D.join

A.int i=s.length();

B. s＞＞＞=3;

C. String ts=s.trim()

D. String t=s+”!”;

A.lilas

B.type

C.maïs

D.lune

A.A是acquired

B.I是ill

C.D是difficult

D.S是syndrome

A.s.replace('.','')

B.s.replace('','.')

C.s=s.replace('.','')

D.s=s.replace('','.')

A、This is the key point.

B、I'm going downtown.

C、He's hiding behind the door.

D、The Old Man and the Sea

A.E → E+T | T T → T*F | F F → (E) | i

B.S → aSa S → bSb S → ε

C.E → E + E E → E * E E → (E ) E → i

D.S → aS S → bS S → ε

A.RTP

B.SIP

C.UDP

D.TCP