our company has a DNS server named server1. Your partner company has a DNS server named server2. You create a stub zone on server1. The master for the stub zone is server2. Serve2 fails. You discover that users are not able to resolve named for the partner company. You need to ensure that users are able to resolve named for the partner company in the event that server2 fails. What should you do?（）

A. Change the stub zone to a secondary zone on server1.
B. Open the SOA record for the zone on server2. Change the minimum (default ) TTL setting to 12 hours.
C. Open the DNS zone for the partner company on server2. Create a new route through (RT) record and a new host (A) record for server1.
D. Open the primary DNS zone on server2. Create a new service locator (SRV) record and a new host (A) record for server1.