Final answer:
Students with previous experience of Class IIA/B are exempted from qualification for Class IIIA/B FWS positions.
Step-by-step explanation:
In this question, the subject is about qualifications for a Class IIIA/B FWS. Students who have previous experience in Class IIA/B are exempted from being qualified on all positions. Therefore, the correct answer is a) Class IIA/B. This means that if a student has previous experience in Class IIA/B, they do not need to go through the qualification process for Class IIIA/B FWS positions.