What should a solutions architect do to meet these requirements?

Explanations:

Pointing to an RDS custom endpoint does not provide the connection pooling and management benefits that RDS Proxy offers. Deploying Lambda functions inside a VPC can lead to cold start issues and does not address the overload of database connections effectively.

Pointing the client driver at an RDS proxy endpoint enables connection pooling and reduces the number of simultaneous connections to the database, improving performance and scalability. Deploying the Lambda functions inside a VPC ensures secure access to the RDS instance while allowing RDS Proxy to manage connections efficiently.

Pointing to an RDS custom endpoint lacks the benefits of connection pooling. Deploying Lambda functions outside a VPC would not allow them to access a private RDS instance, violating connectivity requirements.

While pointing to an RDS proxy endpoint is correct for connection pooling, deploying Lambda functions outside a VPC would prevent access to a private RDS instance. This configuration is not viable for the required database access.