Explanation
The two actions that an architect should recommend to UC are to build a custom Visualforce page for both the change password and forgot password experiences and to build a custom Visualforce page for the change password experience and a community builder page for the forgot password experience. A custom Visualforce page is a page that uses Visualforce markup and Apex code to create a custom user interface. A community builder page is a page that uses the Community Builder tool to create a custom user interface with drag-and-drop components. Both types of pages can be used to modify the look and feel of the password management features for partner community users. However, using a custom Visualforce page for both features requires more coding and customization, while using a community builder page for the forgot password feature allows more flexibility and configuration options.
References: [Visualforce Pages], [Community Builder Pages], [Customize Password Management Features]

Explanation
To register and authenticate new customers on the website using Salesforce Identity, the identity architect should use Delegated Authentication and Embedded Login. Delegated Authentication is a feature that allows Salesforce to delegate the authentication process to an external service, such as a custom website, instead of validating the username and password internally. Embedded Login is a feature that allows Salesforce to embed a login widget into any web page, such as a custom website, to enable users to log in with their Salesforce credentials. The other options are not relevant for this scenario. References: Delegated Authentication, Embedded Login

Explanation
To meet the requirements of using a central cloud-based IAM service for authentication and user management, the IAM architect should implement Salesforce Sales Cloud as a SAML service provider and enable SCIM for provisioning and deprovisioning of users. SAML is a protocol that allows users to authenticate and authorize with an external identity provider and access Salesforce resources. By configuring Salesforce as a SAML service provider, the IAM architect can use the central IAM service as an identity provider and enable single sign-on for users. SCIM is a standard that defines how to manage user identities across different systems. By enabling SCIM in Salesforce, the IAM architect can synchronize user data between the central IAM service and Salesforce and automate user provisioning and deprovisioning based on the changes made in the central IAM service. References: SAML Single Sign-On Settings, SCIM User Provisioning for Connected Apps

Explanation
Login Discovery Page and Embedded Login Page are two valid login page types for Experience Cloud sites.
Login Discovery Page allows users to choose their preferred login method, such as username/password, SSO, or social sign-on. Embedded Login Page allows users to log in from any site page without being redirected to a separate login page. References: Login Discovery Page, Embedded Login

Explanation
Service-provider-initiated SSO is required to support deep linking, which is the ability to direct users to a specific page within Salesforce from a different app. With service-provider-initiated SSO, the user requests a resource from Salesforce (the service provider), which then redirects the user to the identity provider for authentication. After the user is authenticated, the identity provider sends a SAML response back to Salesforce, which then grants access to the requested resource. Web server OAuth SSO flow is used for OAuth
2.0 authentication, not SAML. Identity-provider-initiated SSO is when the user logs in to the identity provider first and then selects a service provider to access. Start URL on identity provider is not a type of authentication flow, but a parameter that can be used to specify the landing page after SSO. References: Certification - Identity and Access Management Architect - Trailhead, Deep Linking, Single Sign On Deep Linking - Salesforce Developer Community