Which command string will set the cards to forward properly?

Your server has two fully functional NIC’s with correct IP configuration. The server is not
forwarding traffic between the NIC’s. Which command string will set the cards to forward properly?

A.
setparam 1 > /proc/sys/net/ipv4/ip_autoconfig

B.
echo 1 > /proc/sys/net/ipv4/ip_forward

C.
set $=1 /proc/sys/net/ipv4/route

D.
cat $1 > /proc/sys/net/ethernet

E.
vi +/1 /proc/sys/net/unix/max_dgram_qlen