Final answer:
External influencers in Mintzberg's theory include regulatory bodies and shareholders, but not Chief Executive Officers, as CEOs are part of the internal organizational structure.
Step-by-step explanation:
Mintzberg's external influencers do not include Chief Executive Officers (CEOs), as CEOs are considered part of an organization's internal structure. Therefore, the correct answer to which external influencers are included in Mintzberg's theory is: regulatory bodies and shareholders. Regulatory bodies oversee and enforce standards, laws, and regulations that organizations must comply with. Shareholders, while they invest in and own part of a company, are not involved in the company's daily operations and therefore influence the company from outside its internal structure. The board of directors is elected by the shareholders and is indeed the first line of corporate governance, playing a significant role in overseeing top executives and ensuring the company operates in the shareholders' best interest. In conclusion, the correct answer is 'a) Shareholders' and 'c) Regulatory bodies'.