Azure provides dynamic scalability for the Azure SQL Databases and Azure Managed Instances.
Azure SQL Database service offers two purchasing models: DTU-based and vCore-based. Azure Managed instance service is based only on the vCore purchasing model. This model allows you to select two scalability parameters for managed instance: the maximum CPU cores and the maximum allocated storage.
(Number 1): When you create a SQL Managed instance or change the resources for an existing instance, you use the Compute + storage panel.
(Number 2): Because Azure SQL Managed Instance uses only the vCore model, you need to select one of the model's Service tier options, General Purpose and Business Critical. These tiers define the storage latency: fast or super fast.
Then, using sliders, you set or change the instance resources: the number of vCores (Number 3) and the storage size (Number 4).
The default values are 8 CPU cores and 256 GB of storage. Azure SQL Managed Instance service will dynamically scale within these parameters to meet the workload demands. All databases in the Azure SQL Managed instance will share the assigned resources.

Option C is incorrect because you need to define a maximum of the resources per database to scale Azure SQL Database for both purchasing models dynamically but not for the Azure SQL Managed Instance scaling.
Option D is incorrect because you need to define a resource limit per group of databases to scale Azure SQL Database Elastic pools dynamically but not for the Azure SQL Managed Instance scaling.
Reference:
https://docs.microsoft.com/en-us/azure/azure-sql/database/scale-resources
https://docs.microsoft.com/en-us/azure/azure-sql/managed-instance/sql-managed-instance-paas- overview
https://docs.microsoft.com/en-us/azure/azure-sql/managed-instance/service-tiers-managed- instance-vcore?tabs=azure-portal