Concept:The BH-series registration is a voluntary scheme for vehicle owners who relocate across States or Union Territories.
Explanation:The Bharat Series (BH-series) was introduced for non-transport vehicles.
It allows free movement of personal vehicles after relocation to a new State or UT.
This facility is available voluntarily to specified categories of individuals.
These categories include defence personnel, Central Government employees, State Government employees, and employees of PSUs or private companies operating in more than four States or UTs.
Therefore, defence personnel, Central Government employees, and State Government employees are all covered.
Answer:D. All of the above