Which statement about licensing and practice is true?

• A. Only a certificate of registration is required
• B. A PhD holder can automatically teach professional subjects
• C. A certificate of recognition is the only document required to practice
• D. To practice, a chemical engineer must hold both a valid certificate of registration and a professional ID card

Answer: (D)

Licensing and practice rely on proving both competence and current authorization. The certificate of registration shows you meet the professional standards and are registered with the regulatory body, while the professional ID card provides a readily verifiable proof of your status as a practicing engineer. This combination ensures you are both qualified and permitted to work, and it helps employers, clients, and authorities recognize and trust your professional identity in the field. Therefore, the requirement to hold both a valid certificate of registration and a professional ID card best explains how licensing and practice work. A single document (certificate alone or recognition alone) does not fully authorize practice, and a PhD does not automatically grant the right to teach professional subjects.