IP multicasting is a set of technologies that enable efficient delivery of data to many locations on a network. Rather than making multiple copies of a message intended to be distributed to multiple recipients at the (71) of origin of a message, multicasting initially sends just one (72) and does not copy it to the individual recipients until it reaches the closest common point on the network, thereby (73) the bandwidth consumed. Network performance is significantly (74) because it isn’t bogged down with the processing and transmission of several large data fries; each receiving computer doesn’t have to (75) the transmitting server for the file.

A．loop

B．find

C．search

D．query

百事可乐往往根据可口可乐的广告费用决定自己的广告费支出，这种广告预算的方法称为______。

A．销售百分百比法

B．利润百分比法

C．目标任务法

D．竞争对抗法