What is an accurate statement about variable prefetching?

What is an accurate statement about variable prefetching?
A . Many blocks that have recently been written to storage by the compute system are retrieved and placed in cache.
B . Many non-contiguous blocks that are not currently required can be retrieved from cache in advance.
C . Storage system prefetches data in multiples of the original I/O request size from the compute system.
D . Storage system prefetches many non-contiguous blocks of data, with varied sizes, from cache.

Answer: D