Which two steps are required for a complete Cisco DNA Center upgrade? (Choose two.)
A. automation backup
B. system update
C. golden image selection
D. proxy configuration
E. application updates
B and E,DNAC 是个大的集成系统,由DNAC本体和上面的application构成,所以要先升级本体,再升级app。https://www.cisco.com/c/en/us/td/docs/cloud-systems-management/network-automation-and-management/dna-center/upgrade/b_cisco_dna_center_upgrade_guide/133x.html