Final answer:
Not all managers and supervisors are required to take an exam administered by the Private Security Board; this varies based on regulatory requirements and the specific industry they are in.
Step-by-step explanation:
The question regarding if all managers and supervisors have to take a written exam administered by the Private Security Board pertains to regulatory requirements within a specific professional context, likely the private security sector. The historical reference to the merit system and civil service examination, such as the requirements of the Pendleton Act, provides a broad perspective on how government jobs have been and are currently filled. Today, most positions within the federal government are appointed based on an applicant's qualifications rather than through mandatory testing. However, key positions that still entail exams are those that demand specialized knowledge or critical thinking abilities. The scenario for private sector entities such as the Private Security Board may differ, as their regulation and examination requirements are typically dictated by industry standards and state laws rather than federal civil service regulations.