Which of the following threat actors is the most likely to use large financial resources to attack critical systems located in other countries?

Nation-state actors are government-sponsored groups with significant resources, including large financial backing, advanced technical capabilities, and often political motivations. Their primary goal is typically espionage, sabotage, or disruption of critical infrastructure in other countries to gain a strategic advantage. An insider is a current or former employee with authorized access, whose motives are usually personal gain or revenge, not large-scale international attacks. An unskilled attacker, or script kiddie, lacks the sophisticated tools and knowledge for such complex operations. Hacktivists are motivated by political or social causes and primarily focus on defacement, denial-of-service, or data leaks to raise awareness, not necessarily large-scale critical system attacks with vast financial resources.