What is a key feature of two-factor authentication?

The key feature of two-factor authentication is that it combines something you know (like a password or PIN) with something you have (such as a hardware token, a smartphone app, or a text message code). This layered approach to security adds an extra level of protection, making it much more difficult for unauthorized users to gain access to an account, even if they have compromised the password. By requiring both elements, two-factor authentication enhances security and significantly reduces the likelihood of unauthorized access.

The other options do not accurately represent the nature of two-factor authentication. Requiring two passwords does not align with the fundamental concept of using different types of verification factors. Additionally, two-factor authentication is not limited to online banking; it is widely used across various applications and services, from social media to corporate networks. Finally, while two-factor authentication greatly improves security, it cannot be completely bypassed; there may still be methods through which it can be circumvented, such as social engineering or phishing attacks.