An area automatically qualifies for designation as an enterprise zone if the area is:
(1) a block group, as defined by the most recent federal decennial census available at the time of designation, in which at least 20 percent of the residents of the block group have an income at or below 100 percent of the federal poverty level;
(2) an area designated by the federal government as a renewal community, a federal empowerment zone, or a federal enterprise community, including any developable area approved by the federal agency responsible for making that designation;
(3) an area located in a distressed county; or
(4) an area inside the boundaries of a defense base development authority established under Chapter 379B, Local Government Code.