HOTSPOT
You have an Exchange Server 2013 organization that contains the servers configured as shown in the following
table.
All of the Exchange servers run Windows Server 2012 R2 and are members of a database availability group
(DAG) named DAG1.
A mailbox database named DB1 replicates between EX1, EX2, EX3, and EX7. The mailbox database copy of
DB1 on EX7 is a lagged database.
You need to ensure that if the number of healthy database copies of DB1 is less than three during a 24-hour
period, the logs in the lagged database replay automatically.
What command should you run? To answer, select the appropriate options in the answer area.
Hot Area:
Answer: 
Explanation:
Lagged copy play down behavior is disabled by default, and can be enabled by running the following command.
Set-DatabaseAvailabilityGroup <DAGName> -ReplayLagManagerEnabled $true
After being enabled, play down occurs when there are fewer than 3 copies.
Lagged copies can now care for themselves by invoking automatic log replay to play down the log files in
certain scenarios:
* When there are fewer than three available healthy copies (active or passive) for more than 24 hours
* When a low disk space threshold is reached
* When the lagged copy has physical corruption and needs to be page patched
Lagged Mailbox Database Copy-Exchange 2013 Enhancements
http://exchangeonline.in/lagged-mailbox-database-copy-exchange-2013-enhancements/