Answer: The correct answer is "C. A company picnic for employees".
Explanation: An internal event is an event to which only people belonging to the same entity, institution or company can attend. For example A company picnic for employees.
An external event is that event in which not only members or employees of a company can attend but also an external public that does not belong to the company in question. For example: An indoor company-sponsored concert that's open to the public.
