Which flows are supported by OAuth in Salesforce?

The correct answer is the combination of the Web Server OAuth flow and User-Agent OAuth flow. These flows are specifically designed to facilitate authentication and authorization in Salesforce.

The Web Server OAuth flow is primarily used for server-to-server communication, allowing a web application to securely obtain an access token on behalf of a user. This flow is appropriate for applications that can keep the client's credentials confidential, such as backend services. It ensures that sensitive information is not exposed during the authentication process, which is crucial for maintaining security in data transactions.

The User-Agent OAuth flow, on the other hand, is designed for applications that run in a user's browser. This flow is useful for web applications where the client cannot keep secrets (like public clients), allowing the user to authenticate using their Salesforce credentials without exposing their credentials to the application itself. Instead, the browser redirects the user to Salesforce for authentication, thus enhancing security.

In the Salesforce ecosystem, these two flows are integral because they allow developers to implement secure integrations and access Salesforce resources while ensuring proper authorization mechanisms are in place that align with OAuth standards. This makes them widely supported and utilized within Salesforce applications for handling user authorizations effectively.