Assuming the swap file /swapdir/swapfile1 has been created, which command can be used to add this file to the available swap space?
A.
swapadd /swapdir/swapfile1
B.
swap -a /swapdir/swapfile1
C.
mount -a /swapdir/swapfile1 /swap
D.
growfs /swap -f /swapdir/swapfile1