The correct answer is: Microservices are used for long running operations while serverless functions are used for short running operations. One of the key differences between microservices and serverless functions is the duration of their execution. Microservices are typically designed to handle long-running operations and may continuously run and process requests as part of a larger system. They are often deployed and managed as long-lived services. On the other hand, serverless functions are designed to handle short-lived operations or tasks that execute in response to specific events or triggers. They are event-driven and execute only when invoked, providing a lightweight and ephemeral computing model. Serverless functions are often used for executing small, isolated pieces of code without the need for managing infrastructure or scaling concerns. While both microservices and serverless functions can be stateless or stateful depending on the specific implementation, the key distinction lies in the typical duration and execution pattern of these components within an application architecture.

In the given scenario, the developer should use the approach of creating an authorizer function using token-based authorization. Token-based authorization is a commonly used approach for authenticating API requests. It involves generating and issuing tokens to API callers, which they can then include in the requests they make to the API. The tokens serve as proof of authentication and are validated by the server to ensure the caller's identity and access rights. By creating an authorizer function using token-based authorization, the developer can implement a custom scheme that accepts string-based parameters from the API caller. This allows the developer to define their own authentication logic and validate the provided tokens according to their requirements. The authorizer function can be configured in the OCI API Gateway to be invoked before forwarding the request to the web application. It will perform the necessary token validation and authentication checks, allowing only authorized requests to access the protected resources of the web application.

The two correct differences between continuous delivery and continuous deployment in the DevOps lifecycle are: Continuous delivery is a process that initiates deployment manually, while continuous deployment is based on automating the deployment process. In continuous delivery, the software is ready for deployment, but the decision to deploy is made manually by a human. On the other hand, continuous deployment automates the deployment process, and once the software passes all the necessary tests and quality checks, it is automatically deployed without human intervention. Continuous delivery utilizes automatic deployment to a development environment, while continuous deployment involves automatic deployment to a production environment. In continuous delivery, the software is automatically deployed to a development or staging environment for further testing and validation. However, the actual deployment to the production environment is performed manually. In continuous deployment, the software is automatically deployed to the production environment, eliminating the need for manual intervention in the deployment process. These differences highlight the level of automation and human involvement in the deployment process between continuous delivery and continuous deployment approaches in the DevOps lifecycle.

The correct answer is: Invoke from the Docker CLI. Executing a function deployed in Oracle Functions is typically done using the following options: Invoke from the Fn Project CLI: The Fn Project CLI provides a command-line interface specifically designed for interacting with Oracle Functions. You can use commands like fn invoke to invoke a function. Trigger by an event in the Oracle Cloud Infrastructure (OCI) Events service: You can configure events in OCI to trigger your function based on various criteria, such as object storage events, resource state changes, or scheduled events. Invoke from the OCI CLI: The OCI CLI (Command Line Interface) allows you to interact with various services in Oracle Cloud Infrastructure, including Oracle Functions. You can use the fn invoke command to invoke a function. Send signed HTTP requests to the function's invoke endpoint: Oracle Functions provides an HTTP endpoint that can be used to invoke functions. You can send signed HTTP requests to this endpoint using tools or programming languages that support making HTTP requests. On the other hand, invoking a function deployed in Oracle Functions using the Docker CLI is not a valid option. The Docker CLI is primarily used for managing Docker containers and images, and it does not provide a direct mechanism for invoking functions in Oracle Functions.

The valid OKE cluster network configuration that meets the requirement of having the least attack surface while still allowing direct access to the deployed applications from the Internet is: Private subnets for nodes and the Kubernetes API endpoint; public subnets for load balancers. By placing the nodes and the Kubernetes API endpoint in private subnets, they are not directly accessible from the Internet, reducing the attack surface. The load balancers, on the other hand, are placed in public subnets, allowing them to be accessed from the Internet and serve as the entry point for accessing the deployed applications. This configuration ensures that the critical components of the cluster, such as the nodes and the API endpoint, are protected within the private network, while still providing accessibility to the applications through the load balancers. It helps to enhance security by limiting direct access to the internal components of the cluster while maintaining the availability of the deployed applications.