A single point of failure is a piece of hsrdware or application that is key to$?$

A$.$ THe success of safegsurds

B$,$ the functioning if an entire system

C$,$ ensurung thst individuald eith proper permissiobs can use the shstem and retrieve data in a dependable manner

D$.$soecufying how ling systems msy be offline before an organization loss money