To block all hosts in the network range of 192.168.160.0 to 192.168.191.0, you need to use a wildcard mask that accurately reflects that range. The appropriate choice would be:
access-list 10 deny 192.168.160.0 0.0.31.255
Explanation:
- The range 192.168.160.0 to 192.168.191.255 consists of a total of 32 addresses starting from 160 to 191 in the third octet.
- The wildcard mask
0.0.31.255
means that you are matching all addresses where the first two octets (192.168) are fixed, the third octet can vary between 160 to 191 (which covers the range of 32 addresses), and the fourth octet can vary from 0 to 255.
This ACE effectively covers the entire range of hosts you intend to block.