What would be the recommended solution to grant mobile app access to sales users?

universal container plans to develop a custom mobile app for the sales team that will use salesforce for authentication and access management. The mobile app access needs to be restricted to only the sales team .

What would be the recommended solution to grant mobile app access to sales users?
A . Use a custom attribute on the user object to control access to the mobile app
B. Use connected apps Oauth policies to restrict mobile app access to authorized users.
C. Use the permission set license to assign the mobile app permission to sales users
D. Add a new identity provider to authenticate and authorize mobile users.

Answer: B