Your network contains an Active Directory domain named contoso.com. Contoso.com contains two domain
controllers named DC1 and DC2. DC1 and DC2 are configured as DNS servers and host the Active Directory-integrated zone for contoso.com.
From DNS Manager on DC1, you enable scavenging for the contoso.com zone.
You discover stale DNS records in the zone.
You need to ensure that the stale DNS records are deleted from contoso.com.
What should you do?

A.
From DNS Manager, enable scavenging on DC1.

B.
From DNS Manager, reload the zone.

C.
Run dnscmd.exeand specify the ageallrecordsparameter.

D.
Run dnscmd.exeand specify the startscavengingparameter.

Explanation:
According to Technet the answer should be A (“From DNS Manager, enable scavenging on DC1”). Scavenging
has been enabled for the zone, but it also needs tebe enabled on the server.
Reference:
http://technet.microsoft.com/en-us/library/cc771677.aspx
Prerequisites for aging and scavenging
Before you can use the aging and scavenging features of DNS, several conditions must be met:
Scavenging and aging must be enabled, both at the DNS server and on the zone.
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