Which of the following describes the authentication methods of RESTlets?

The correct answer highlights that RESTlets in NetSuite support multiple authentication methods, including OAuth. This flexibility is significant because OAuth enables secure delegated access for users, allowing applications to interact with NetSuite on behalf of a user without sharing passwords. It provides a more secure way to connect and manage permissions, especially in scenarios where third-party applications might need limited access to a NetSuite account.

In addition to OAuth, RESTlets can also use other methods such as token-based authentication, allowing for secure interactions without compromising user credentials. This versatility is crucial for developers and organizations that require varying levels of access and security depending on different use cases or integration scenarios.

The other options provided do not capture the accurate capabilities of RESTlets' authentication methods; focusing solely on a single method like single sign-on or password would limit integration possibilities and security options available for developers. It's essential for users to understand the variety of authentication methods available to best suit their integration needs while maintaining robust security practices.