We initially described SOA without mentioning Web services，and vice vers

A.This is because they are orthogonal service-orientation is an architectural（ 1 ），while Web services are an implementation（ 2 ）.The two can be used together，and they frequently are，but they are not mutually dependent.For example,although it is widely considered to be a distributed-computing solution,SOA can be applied to advantage in a single system,where services might be individual processes with well-defined（ 3 ）that communicate using local channels，or in self-contained cluster，where they might communicate across a high-speed interconnect.Similarly, while Web services are （ 4 ）as the basis for a service-oriented environment，there is nothing in their definition that requires them to embody the SOA principles.While （ 5 ）is often held up as a key characteristic of Web services，there is no technical reason that they should be stateless—that would be a design choice of the developer，which may be dictated by the architectural style of the environment in which the service is intended to participate.A.design

B.style

C.technology

D.structure