问题：

[单选]

You are the administrator of a Windows 2000 network. The network consists of a Windows 2000 domain named ExamSheet.net. You install Windows 2000 Professional on a new computer named ES1 and configure the TCP/IP settings to have a static IP address. You plan to join ES1 to the ExamSheet.net domain. You configure two DNS server addresses in the TCP/IP properties. The first DNS server address is for a DNS server hosted by your ISP, the second DNS server address is for a DNS server authoritative for the ExamSheet.net domain. When you attempt to join ES1 to the domain, you are unable to do so. You can successfully PINGthe IP address of each DNS server from ES1. You want ES1 to be able to join the tesking.com domain. 
What should you do? （）

A . Delete the second DNS server entry.
B . Delete the first DNS server entry.
C . Add an A （host） record for the computer to the appropriate DNS zone.
D . Configure the computer toObtain an IP address automatically.