The face of the identification card for persons with disabilities shall bear the word "TRANSPORTATION" with a box or blank space adjacent thereto. The issuer of the card shall place an "X" in such box or blank space if the applicant's disability creates mobility limitations which prevent him or her from climbing stairs or otherwise from entering normally designed buses or other vehicles normally used for public transportation. When so marked, the identification card for persons with disabilities shall serve as sufficient proof of the need for special transportation services for persons with disabilities provided by any entity in this state.