Which of the following commands will copy one disk partition /dev/sda3 to /dev/sdb3?

A.
dd if=/dev/sdb3 of =/dev/sda3 bs=4096 conv=notrunc

B.
dd if=/dev/sda3 of=/dev/sdb3 bs=4096 conv=notrunc

C.
dd –input /dev/sda3 –output /dev/sdb3 bs=4096 conv=notrunc

D.
dd –input /dev/sdb3 –output /dev/sda3 bs=4096 conv=notrunc

Explanation:
From the man pages:
dd – convert and copy a file
SYNOPSIS
dd [OPERAND]…
dd OPTION
DESCRIPTION
Copy a file, converting and formatting according to the operands.
bs=BYTES read and write BYTES bytes at a time (also see ibs=,obs=)
if=FILE read from FILE instead of stdin
of=FILE write to FILE instead of stdout