在同一总体中进行抽样研究，随着样本含量增大，则（）

A.标准差增大

B.标准误增大

C.标准差趋向0

D.标准差减小

E.标准误减小

Packet switching is a method of slicing (71) messages into parcels called“packets，”sending the packets along different communication (72) as they become available，and thenreassembling the packets (73) they arrive at their destination．Prior to the development ofpacket switching，early computer networks used leased，dedicated telephone circuits to (74) with terminals and other computers．In circuit—switched networks such as the telephone system，a complete point—to—point (75) is put together,and then communication can proceed．

A．link
B．talk
C．communicate
D．connect