单项选择题

A.Run the dnscmd /clearcache on server3.
B.Run the ipconfig /flushdns command on server3.
C.Decrease the time-to-live (TTL) on the start of authority (SOA) record of na.contoso.com to 15minutes.
D.Increase the retry interval value on the start of authority (SOA) record of na.contoso.com to 15 minutes.