What is phishing primarily used for?

Phishing is primarily used to obtain sensitive information by posing as a trustworthy entity, which is why the correct answer focuses on this aspect. Phishing attacks typically involve fraudulent communications, often through email, that appear to be from reputable sources—such as banks, online services, or other legitimate organizations.

The attackers aim to gain the victim's trust so that they will unknowingly provide personal information, such as usernames, passwords, credit card details, and other sensitive data. This deception capitalizes on social engineering techniques, where attackers manipulate human psychology to exploit the victim’s trust or fear.

In contrast, the other provided options refer to different security concepts or malicious activities that are not directly related to the primary purpose of phishing. For example, limiting access to email systems is more about enforcing security measures and authentication, while stealing data through network intrusion involves more direct hacking techniques. Additionally, corrupting email databases is tied to virus propagation and malware, which are distinct from the deceptive tactics employed in phishing attacks.