You are evaluating the implementation of a Database Availability Group (DAG).
You need to recommend changes to the planned implementation to minimize the loss of large email messages
if a single DAG member fails.
What should you recommend changing?

A.
The preference of the mail exchanger (MX) records

B.
The duration of single item recovery

C.
The intervals of shadow redundancy

D.
The size of the transport dumpster

Explanation:
Shadow redundancy intervals will need to be ammended
SafetyNet is a component of Shadow Redundancy. -> .http://technet.microsoft.com/en-us/library/dd351027
(v=exchg.150).aspx
Example 1:
ShadowResubmitTimeSpan on Set-TransportConfig
3 hours
How long a server waits before deciding that a primary server has failed and assumes ownership of shadow
messages in the shadow queue for the primary server that’s unreachable.
Example 2:
SafetyNetHoldTime on Set-TransportConfig
2 days
How long successfully processed messages are retained in Safety Net. Unacknowledged shadow messages
eventually expire from Safety Net after the sum of SafetyNetHoldTime and MessageExpirationTimeout on SetTransportService.