The SiRT featured is enabled on the RA in an SRDF/S configuration. When does the host
receive the acknowledgement of a write?

A.
IO is written to the cache at the R2 site and acknowledgement is received by the R1 site
from R2 site.

B.
IO is written at R1 site cache and is sent to the R2 site.

C.
IO is written to R2 site cache but not acknowledged yet.

D.
Immediately after the IO is written to R1 cache.