Your company has a main officeand five branch officesthat are connected by WAN links.
The company has an Active Directory domainnamed contoso.com.
Each branch officehas a member serverconfigured as a DNS server.
All branch office DNS servers host a secondary zonefor contoso.com.
You need to configure the contoso.com zone to resolve client queries for at least four days in the event
that a WAN link fails.
What should you do?

A.
Configure the Expires after option for the contoso.com zone to 4 days.

B.
Configure the Retry interval option for the contoso.com zone to 4 days.

C.
Configure the Refresh interval option for the contoso.com zone to 4 days.

D.
Configure the Minimum (default) TTL option for the contoso.com zone to 4 days.

Explanation:
http://technet.microsoft.com/en-us/library/cc816704%28v=ws.10%29.aspx
Adjust the Expire Interval for a Zone
You can use this procedure to adjust the expire interval for a Domain Name System (DNS) zone. Other DNS
servers that are configured to load and host the zone use the expire interval to determine when zone data
expires if it is not successfully transferred. By default, the expire interval for each zone is set toone day.
You can complete this procedure using either the DNS Manager snap-in or the dnscmd command-line tool.
To adjust the expire interval for a zone using the Windows interface
1. Open DNS Manager. To open DNS Manager, click Start, point to Administrative Tools, and then click
DNS.
2. In the console tree, right-click the applicable zone, and then click Properties.
3. On the General tab, verify that the zone typeis either Primary or Active Directory-integrated.
4. Click the Start of Authority (SOA) tab.
5. In Expires after, click a time period in minutes, hours, or days, and then type a number in the text box.
6. Click OK to save the adjusted interval.