A. To file as a candidate for any county office, a person must have been a registered voter and have maintained a current principal residence within the county for the six-month period immediately preceding the first day of the filing period prescribed by law. B. To file as a candidate for the office of county commissioner, a person must have been a registered voter within the county commissioner district and have maintained a current principal residence within such district for the six-month period immediately preceding the first day of the filing period prescribed by law. C. For purposes of this section, evidence of a "principal residence" may include, but not be limited to, the address listed on:
1. A federal or state tax return;
2. A driver license; or 3. An automobile registration.