An administer wants to use the MCAUSER field in the server-connection channel definition to
control access by the client application.

This can be achieved by setting MCAUSER to:

A.
Blank

B.
The user ID mqm

C.
An invalid user ID

D.
A user ID which has the required access for client applications

Explanation:
http://pic.dhe.ibm.com/infocenter/wmqv7/v7r0m0/index.jsp?topic=%2Fcom.ibm.mq.csq
zaf.doc%2Fcs11910_.htm