When designing a Dell EMC Unity 550F, what is the maximum number of enclosures and drive slots per bus?
A. 10 enclosures and 250 drive slots
B. 10 enclosures and 500 drive slots
C. 15 enclosures and 275 drive slots
D. 15 enclosures and 1000 drive slots
Reference: https://www.emc.com/collateral/TechnicalDocument/docu69319.pdf