In the dual engine configuration of OceanStor Dorado 18000,data can still be accessed even if multiple controllers fail. The OceanStor Dorado 18000 can handle which of the following failure scenarios? (Multiple choice)
A . A single controller fails
B . Two controller fail simultaneously at the same time point
C . A single engine fails
D . Up to seven controllers fail simultaneously at the time point
Answer: ABCD