What is the difference between the usage of BUFFSIZE= and BUFNO= options?

The following SAS program is submitted:

data new(bufsize = 6144 bufno = 4);

set old;

run;

What is the difference between the usage of BUFFSIZE= and BUFNO= options?
A . BUFSIZE=specifies the size of the output buffer in kilobytes; BUFNO=specifies the number of output buffers
B . BUFSIZE= specifies the size of the input buffer in bytes; BUFFNO= specifies the number of input buffers
C . BUFSIZE= specifies the size of the input buffer in kilobytes; BUFNO=specifies the number of input buffers
D . BUFSIZE= specifies the size of the output buffer in bytes; BUFNO= specifies the number of output buffers

Answer: D