Which outbound access list, applied to the WAN interface of a router, permits all traffic...

The correct answer is A.

Block HTTP traffic (TCP port 80)

Source: 10.10.10.1

Destination: any

Permit all other traffic

ip access-list extended 100

deny tcp host 10.10.10.1 any eq 80

permit ip any any

deny tcp host 10.10.10.1 any eq 80 → Blocks HTTP traffic from 10.10.10.1 to any destination

permit ip any any → Allows all other traffic

This perfectly matches the requirement.

B. ip access-list extended 10 ❌ Invalid — extended ACLs use ranges 100–199 or named ACLs, not 10

C. ip access-list extended NO_HTTP ❌ Missing permit ip any any → implicit deny all at the end blocks everything

D. deny tcp host 10.10.10.1 eq 80 any ❌ Incorrect syntax/order

eq 80 is applied to destination port, not source

This line is malformed and does not match HTTP filtering correctly

ACL evaluation rules:

Top-down processing

First match wins

Implicit deny all at the end

Correct pattern for “block one thing, allow rest”:

deny < specific traffic >

permit ip any any