Final answer:
The protocol that enables SSO between AWS and Salesforce is SAML, which facilitates secure and streamlined login processes for users by allowing identity providers to pass credentials to service providers.
Therefore the correct answer is option D saml.
Step-by-step explanation:
Alicia and her business partners are seeking to set up Single Sign-On (SSO) between their AWS account and Salesforce. The protocol that makes this possible is SAML (Security Assertion Markup Language). SAML is an open standard that allows identity providers (in this case, AWS) to pass authorization credentials to service providers (like Salesforce).
This means that with SAML, Alicia can streamline the access process to salesforce, allowing for automated and secure logins without the need to manage multiple sets of user credentials. Implementing SSO via SAML would ensure a seamless experience for all the sales reps and partners utilizing the Salesforce subscription for tracking their sales efforts.