Answer:
C. Because insiders create threats after incidents at their places of employment
Explanation:
Option A is not correct because insiders do have the knowledge of computers and network to perform task in a company. Some company employee belong to the IT department, so they do have the knowledge of computer and network.
Option B is also not correct. Though insiders are likely to change content to make a political statement, it will be against any company policy because an employee in a company should maintain political neutrality as mostly stated in any company policy.
Option D is also not correct. Insiders will not like to cause disruption and panic among citizens because mostly likely the company is offering services to the citizens, so why disrupt where you are benefitting from.
Option C is the correct option as the company actually lay off some employee, so it is most likely that they will create threats after the laying off incident at their place of work.