If your machine is not used as a server and is not on a local network, what packet-filtering strategy should you use? A. Block all ports except 80. B. Do not block any ports. C. Block all ports. D. Do not block well-known ports.

Block all ports except 80

Explanation:

We can make our network more defensive by blocking all ports except 80. This strategy can reduce the risk of attackers. If all the ports that are not in used are not in used can make system or network insecure. To enhance the security and reduce the risk of attacks we block all the ports that are not in used.

Using this strategy on people visit who need the data and attacker cannot access the system, without consent of owner.