Answer : 4. "हैकिंग"
Explanation :

There are many types of cyber threats, including:

1. Spam Email: Spam email is a type of cyber threat which is done by sending unsolicited emails. Spam emails are often used to spread advertisements, scams, or viruses.

2. Hacking: Hacking is a type of cyber threat that involves gaining unauthorized access to a computer system or network. Hackers often use hacking to steal data, damage systems, or intercept transactions.

3. Phishing: Phishing is a type of cyber threat in which victims are tricked into providing their personal information, such as passwords or credit card numbers. Phishing attacks are often carried out via email, social media, or websites.

4. Viruses: Viruses are a type of malware that can infect a computer system and damage data, slow down the system, or even disable it. Viruses often spread through spam emails, infected files, or physical media.

5. Worm: A worm is a type of malware that can copy itself from a computer system and spread from one system to another. Worms often spread via email, infected files, or physical media.

6. Denial-of-Service (DoS) attacks: DoS attacks are a type of cyber threat that is used to disable a website or service. DoS attacks are often carried out using large amounts of traffic or resources.

7. Load Ballast Attacks: Load ballast attacks are a type of DoS attack in which a large amount of data is sent to a website or service. Load ballast attacks are often carried out to disable a website or service.

8. Human-based attacks: Human-based attacks are a type of cyberattack that target people. Human-based attacks can include phishing, social engineering, and cyberpsychology.

9. Physical Attacks: Physical attacks are a type of cyberattack that targets the physical components of a computer system or network. Physical attacks could include data centre fires or power outages.