Your company has an Active Directory forest. Not all domain controllers in the forest are  configured as Global Catalog Servers. Your domain structure contains one root domain and one  child domain.
You modify the folder permissions on a file server that is in the child domain. You discover that  some Access Control entries start with S-1-5-21... and that no account name is listed.
You need to list the account names. 
What should you do（）

Your company has a main office and 10 branch offices. Each branch office has an Active  
Directory site that contains one domain controller. Only domain controllers in the main office are  configured as Global Catalog servers.    
You need to deactivate the Universal Group Membership Caching option on the domain  controllers in the branch offices.  
At which level should you deactivate the Universal Group Membership Caching option（）