Explanation
The following considerations should be reviewed before implementing Flow for customer onboarding:
Use Field Level Security on Milestones, which is a setting that controls whether users can view and edit fields on records. The Admin should use Field Level Security to restrict access to the Milestones field on the Flow Template object, which is used to track the progress of customer onboarding flows2.
Flow for Financial Service Cloud is not available for the Individual Object Model, which is an alternative data model that uses the Individual object instead of Person Accounts to store information about people. Flow for Financial Service Cloud only supports Person Accounts as the primary object for customer onboarding flows2. Verified References: 2

Explanation
The following statements are true for a Group in Financial Services Cloud:
Financial Services Cloud includes a group record type for households, which is a record type that represents a collection of individuals who share financial goals, such as family members or roommates.
A group is a type of account record that people and businesses can be related to through the account contact relationship object, which is a junction object that links an account to a contact or an individual and defines their role or relationship with that account.

Explanation
To modify a published Action Plan to support an additional task, Jen should use the Action Plan item feature to add an additional task to the published Action Plan. An Action Plan item is a construct in Financial Services Cloud that allows you to add, edit, or delete tasks in an existing Action Plan. You can use Action Plan items to customize your Action Plans according to your specific needs and preferences. Verified References: :
Salesforce Help Article 1

Explanation
The most suitable option for Cumulus Cloud Bank to provide its customer service staff with real-time access to customer accounts, including the ability to view current transactions and balances, is to embed custom Lightning web components on the Account and Financial Account pages, and use custom Apex to make callouts to the core system services. This option allows the bank to leverage the Lightning Platform features and capabilities, such as Lightning web components, Apex, and callouts, to create a seamless and performant integration with their core systems. By using custom Lightning web components, the bank can create custom user interfaces that display the data from the core systems on the Account and Financial Account pages. By using custom Apex, the bank can write code that makes callouts to the core system services using HTTP requests and responses, and handle any authentication, error handling, or data transformation logic.

Explanation
To configure Financial Services Cloud to allow users to relate two business accounts, the administrator should update the Role picklist on the Account-Account Relationship object with new value. The Role picklist is a field on the Account-Account Relationship object that defines the type of relationship between two accounts, such as Household Member, Business Owner, Trustee, or Friend. The Role picklist is used to filter and display the account-account relationships in the Actionable Relationship Center (ARC). To update the Role picklist, you need to go to Setup > Object Manager > Account-Account Relationship > Fields & Relationships > Role and add or remove values according to your business needs. Verified References: : Salesforce Help Article
[10] : Salesforce Help Article [11]