Explanation
The web application should be hosted on a secure server and the web server must be able to protect consumer privacy are two considerations that an architect should point out to UC. To integrate an external web app with the Salesforce API, UC can use the OAuth 2.0 web server flow, which implements the OAuth 2.0 authorization code grant type4. With this flow, the server hosting the web app must be able to protect the connected app's identity, defined by the client ID and client secret4. The web application should be hosted on a secure server to ensure that the communication between the web app and Salesforce is encrypted and protected from unauthorized access or tampering6. The web server must be able to protect consumer privacy to comply with data protection laws and regulations, such as GDPR or CCPA . The web server should implement best practices for storing and handling user data, such as encryption, hashing, salting, and anonymization. The flow involves passing the user credentials back and forth is not a correct consideration, as the web server flow does not require the user credentials to be passed between the web app and Salesforce. Instead, it uses an authorization code that is exchanged for an access token and a refresh token4. The flow will not provide an OAuth refresh token back to the server is also not a correct consideration, as the web server flow does provide a refresh token that can be used to obtain new access tokens without user interaction4. References: OAuth 2.0 Web Server Flow for Web App Integration, Secure Your Web Application, [General Data Protection Regulation (GDPR)], [California Consumer Privacy Act (CCPA)],
[Data Protection Best Practices]