Explanation
Reference and details below.

The FHIR R4 Patient API is a Health Cloud feature that allows users to create, update, and query patient data in Salesforce using the Fast Healthcare Interoperability Resources (FHIR) standard1. FHIR is a widely adopted standard for exchanging healthcare information electronically2. By using the FHIR R4 Patient API, Bloomington Caregivers can make their patient clinical data available to the external payer in a cost-effective and interoperable way, without requiring any custom development or third-party tools. The FHIR R4 Patient API supports the US Core Patient profile, which defines the minimum set of data elements for exchanging patient information3.
Reference:
1: FHIR Patient Input | Salesforce Health Cloud Developer Guide | Salesforce Developers

Coverage data model (B) is the data model that is used to represent information via standard object and record types on standard objects to manage how care is covered. Health Insurance data model (A), Payer data model , Plan data model (D), and Benefit data model (E) are not valid data models in Health Cloud.

Advanced Therapy Management can help the pharma company with its personalized medicine programs, as it enables them to coordinate the various steps involved in the process, such as apheresis and infusion. Advanced Therapy Management provides a set of features and tools that allow users to create and manage complex care plans, track the progress of each patient, and monitor the inventory and logistics of the therapy products.

According to the Health Cloud Implementation Guide, a Health Cloud administrator can change the default sub-tab when opening a record by going to setup, navigating to Custom Settings, and editing the Default Subtab setting. This setting allows you to specify which sub-tab should be displayed by default when opening a record in Health Cloud - Console. The other options are not relevant for changing the default sub-tab.