C and D. Web Service data is XML in a SOAP package.
A2:
B. <cfinvoke> is used to invoke ColdFusion Components and Web Services. A is incorrect, as <cfinvoke> handles its own HTTP calls internally. C is incorrect, as only CFCs can be instantiated as objects, not Web Services. D is incorrect, as all Web Services' XML processing is handled by ColdFusion internally.
A3:
A, B, and D. For a CFC function to be accessed as a Web Service, it must be named using NAME, access must be set with access="remote", and the RETURNTYPE must be specified too.
