● A （  ）is an independent  firm that offers connection and transaction-forwarding services to buyers and sellers engaged in EDI.

（71）A．  WAN

B.  LAN

C.  VPN

D.  VAN

● Businesses have also been engaging in a type of electronic commerce , (  ) occurs when one business transmits computer-readable data in a standard format to another business.

（72）A．  EFT

B.  EDI

C.  ERP

D.  CRM

● Today  it  is  common  to  access  the  Internet  from  a  variety  of (  ) devices  like smartphones and tablets.

（73）A．  mobile

B.  move

C.  moving

D.  shift

● For data transmission to be successful，sending and receiving devices must follow a set of communication rules for the exchange of information. These rules are known as  (  )。

（74）A．  E-mail

B.  Intemet

C.  network

D.  protocols

● Computer (  ) focuses  on  protecting   information ，hardware ，and  software  from unauthorized use and damage.

（75）A．  network

B.  virus

C.  security

D.  architecture