单选题：Buffering is done for reason(s):

Buffering is done for reason(s): @[D](1)
A. To cope with device speed mismatch
B. To cope with devices that have different data-transfer sizes
C. To support copy semantics for application I/O
D. All of A, B and C



A.To cope with device speed mismatch
B.To cope with devices that have different data-transfer sizes
C.To support copy semantics for application I/O
D.All of A, B and C


答案：D