Option A is correct because enabling SSO on both Service Cloud and Marketing Cloud is a necessary step to allow agents to authenticate and access all systems with the least possible clicks, as they only need to log in once with their credentials and then switch between systems seamlessly.
Option B is correct because defining which system is acting as an identity provider (IDP) is a necessary step to configure SSO between Service Cloud and Marketing Cloud, as it determines which system will verify the identity of the agents and issue authentication tokens for the other system.
Option E is correct because enabling MFA on the identity provider (IDP) is a necessary step to meet the company's requirement of confirming the identity of the agents using multi-factor authentication (MFA) upon logging in to either system. MFA adds an extra layer of security by requiring agents to enter a verification code or use another device besides their username and password.
Option C is incorrect because configuring Marketing Cloud Connect is not a necessary step to enable SSO between Service Cloud and Marketing Cloud, as it is used for data synchronization and integration purposes, not for authentication or access management.
Option D is incorrect because enabling Active Directory Federation Services (ADFS) and Salesforce Event Monitoring on the identity provider (IDP) are not necessary steps to enable SSO between Service Cloud and Marketing Cloud, as they are used for different purposes. ADFS is used for federating identities across different domains or organizations, while Salesforce Event Monitoring is used for tracking user activity and performance within Salesforce.
Reference:
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The Secondary Instance Group is used for sandboxes in B2C Commerce. Adding new sandboxes to this group does not require creating a new realm or adding instances to the Primary Instance Group, which is used for production and staging instances. Reference: https://developer.salesforce.com/docs/commerce/b2c-commerce/guide/b2c-developer-sandboxes.html

This answer is correct because core profile data (name, email) should be maintained within Experience Cloud as the primary system when using communities as an identity provider (IDP) for commerce. This ensures that customers have a consistent identity across both platforms and can access self-service support features in communities. Reference: https://help.salesforce.com/s/articleView?id=sf.b2c_commerce_service_cloud_integration.htm&type=5

Salesforce Shield Encryption is a feature that allows encrypting sensitive data at rest in Salesforce without compromising functionality or performance. Shield Encryption uses probabilistic encryption to protect data while preserving its format and length. Field-Level Encryption is a feature in Marketing Cloud that allows encrypting sensitive data at rest in Marketing Cloud using customer-managed keys. Field-Level Encryption uses deterministic encryption to protect data while preserving its format and length. When determining an appropriate solution for encrypting specific fields in Service Cloud as well as in data extensions in Marketing Cloud, the following considerations are relevant:
With Shield, encrypted fields cannot be used to filter or sort in Process Builder and Flow Builder. Process Builder and Flow Builder are tools in Salesforce that allow creating automated workflows and processes based on certain criteria or conditions. However, Shield Encryption does not support filtering or sorting on encrypted fields in these tools, because probabilistic encryption does not allow exact matching or comparison of values.
Shield encryption can be done on any standard or custom field on all field types, but cannot be set to encrypt those fields in Marketing Cloud. Shield Encryption supports encrypting any standard or custom field on any field type in Salesforce, such as text, email, phone, date, etc. However, Shield Encryption does not apply to Marketing Cloud fields or data extensions, because they are stored in a separate database from Salesforce. To encrypt fields in Marketing Cloud, Field-Level Encryption must be used.
Option A is incorrect because with Shield, encrypted fields are visible to the user if they have the View Encrypted Data permission, but there are other feature impacts such as filtering, sorting, searching, etc. Option C is incorrect because Field-Level Encryption is not required on Marketing Cloud to encrypt the custom fields if they are already encrypted by Shield Encryption in Service Cloud. However, Field-Level Encryption can be used on Marketing Cloud if additional encryption or customer-managed keys are needed. Reference:
https://help.salesforce.com/s/articleView?id=sf.security_pe_overview.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.security_pe_considerations_general.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.mc_overview_field_level_encryption.htm&type=5

These answers are correct because they are recommendations that can help ensure that customer experiences are compliant with all domestic and international regulations related to data privacy and security. Providing shoppers a mechanism to download their data can help comply with the right to access and portability under GDPR and other laws. Implementing Customer Data Platform (CDP) can help comply with data protection laws by providing tools to manage consent, preferences, and identity resolution across multiple channels and touchpoints. References: https://help.salesforce.com/s/articleView?id=sf.b2c_commerce_gdpr.htm&type=5
https://www.salesforce.com/products/customer-data-platform/overview/