Which of the following commands enables ip forwarding permanently?

Echo "1" > /proc/sys/net/ipv4/ip_forward

Open the file /etc/sysctl.conf and insert net.ipv4.ip_forward=1 in the file

Open the file /etc/sysctl.conf and insert net.ipv4_forward=0 in the file

Open the file /etc/sysctl.conf and insert net.ipv4.icmp_echo_ignore_all=1 in the file

Answer:
Open the file /etc/sysctl.conf and insert net.ipv4.ip_forward=1 in the file

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