Answer:
C. Inside attack
Step-by-step explanation:
An inside attack is driven by an internal user who has access to the entity's systems. Internal users include employees and contractors who have authorized access to the systems of an entity. An inside attack can be intentional e.g. by malicious employees who intend to interrupt system operations or the attack may be accidental e.g by a poorly trained intern who carelessly disrupts an entity's system but with no malicious intent.