You are debugging a Windows Communication Foundation (WCF) service. The service uses signed and encrypted messages.
You need to configure logging so that you can read the contents of the messages. What should you do?

A.
Set maxSizeMessagesToLog to 10

B.
Set logMessageAtServiceLevel to true.

C.
Set maxMessagesToLog to 10.

D.
Set logMessageAtTransportLevel to true.

Explanation:
Configuring Message Logging
(http://msdn.microsoft.com/en-us/library/ms730064.aspx)

Service Level
Messages logged at this layer are about to enter (on receiving) or leave (on sending) user code.
If filters have been defined, only messages that match the filters are logged.
Otherwise, all messages at the service level are logged. Infrastructure messages (transactions, peer channel, and security)
are also logged at this level, except for Reliable Messaging messages. On streamed messages, only the headers are logged.
In addition, secure messages are logged decrypted at this level.

Transport Level
Messages logged at this layer are ready to be encoded or decoded for or after transportation on the wire.
If filters have been defined, only messages that match the filters are logged. Otherwise, all messages at the transport layer are logged.
All infrastructure messages are logged at this layer, including reliable messaging messages. On streamed messages,
only the headers are logged. In addition, secure messages are logged as encrypted at this level, except if a secure transport such as HTTPS is used.