This pattern uses a non-capturing group with an alternation (|) for each of the eight target strings. Each static target is escaped as needed so that special characters (such as . + ( ) [ ] ? :) are matched literally. The anchors ^ and $ ensure that only an exact match of one of the alternatives is found, thus excluding any other strings in the challenge text. For example, the plus sign in email or phone numbers is escaped (\+), periods in domain names are escaped (\.); similarly, special sequences in the URL and IPv6 address are carefully escaped. This approach guarantees that only the exact eight target strings are matched by the regex.