Which line should be added to smb.conf to avoid UID and GID inconsistencies across servers over SMB?

A.
ldap dn = ldap://ldapserver.com

B.
ldap server = ldap://ldapserver.com

C.
idmap backend = idmap_rid:BUILTIN=ldapserver.com

D.
idmap backend = ldap:ldap://ldapserver.com

E.
ldap passwd sync = ldapserver.com