Your network contains an Active Directory domain named adatum.com. The domain
contains a domain controller named DC1. DC1 has an IP address of 192.168.200.100.
You need to identify the zone that contains the Pointer (PTR) record for DC1.
Which zone should you identify?

A.
adatum.com

B.
_msdcs.adatum.com

C.
100.168.192.in-addr.arpa

D.
200.168.192.in-addr.arpa

Explanation:
Reference 1)
MCTS 70-640 Cert Guide: Windows Server 2008 Active Directory, Configuring (Pearson IT
Certification, 2010) page 57
Reverse lookup: This occurs when a client computer knows the IP address of another
computer and requires its hostname, which can be found in the DNS server’s PTR (pointer)
resource record.
Reference 2)

MCTS 70-640 Cert Guide: Windows Server 2008 Active Directory, Configuring (Pearson IT
Certification, 2010) page 45/730
You are configuring a reverse lookup zone for your network, which uses the Class C network
address range of 192.168.5.0/24. Which of the following addresses should you use for the
reverse lookup zone?
a. 5.168.192.in-addr.arpa
b. 0.5.168.192.in-addr.arpa
c. 192.168.5.in-addr.arpa
d. 192.168.5.0.in-addr.arpa
The reverse lookup zone contains octets of the network portion of the IP address in reverse
sequence and uses a special domain name ending in in-addr.arpa. Thus the correct address
is 5.168.192.in-addr.arpa. You do not use the host portion of the IP address, so
0.5.168.192.in-addr.arpa is incorrect. The octets must be specified in reverse sequence, so
the other two choices are both incorrect.