Which two actions ensure that the switches upgrade one at a time?

Refer to the exhibit.

A client configures an upgrade of its Cisco Nexus switches that are connected to the Cisco ACI controller, such that the switches are upgraded one at a time. After the upgrade is run, it is discovered that both Cisco Nexus switches were upgraded simultaneously .

Which two actions ensure that the switches upgrade one at a time? (Choose two.)
A . Configure the *Do not pause on failure and do not wait on cluster health" Run Mode
B . Choose the ‘Pause upon upgrade failure" Run Mode
C . Select the "Graceful Maintenance" checkbox
D . Place each leaf switch in a different upgrade group
E . Check the Ignore Compatibility" checkbox

Answer: B,D

Explanation:

Reference: https://www.cisco.com/c/en/us/td/docs/unified_computing/ucs/ts/guide/UCSTroubleshooting/UCSTroubleshooting_chapter_0100.html