What an Application Developer Can't Do in the Developer Portal

C.

The Developer Portal in Oracle API Platform Cloud Service is a web-based interface that allows application developers to consume APIs, manage their subscriptions, and access resources related to APIs. It is a self-service platform that empowers developers to discover APIs, learn how to use them, and start building applications.

Let's go through the given answer options one by one to determine which activity an application developer cannot perform in the Developer Portal:

A. Monitor performance: An application developer can monitor the performance of the APIs they consume through the Developer Portal. The portal provides performance metrics, such as response time, error rate, and usage statistics, that allow developers to track the behavior of their API calls.

B. Subscribe to a plan: Application developers can subscribe to a specific plan to consume APIs from the Developer Portal. The portal displays different subscription plans, along with their pricing and usage limits, that developers can choose from based on their requirements.

C. Create an API: Creating an API is a task that is typically performed by an API provider or an API administrator, not an application developer. Therefore, creating an API is not an activity that an application developer can perform in the Developer Portal.

D. Learn about APIs: The Developer Portal provides a comprehensive set of resources, such as documentation, tutorials, and forums, that allow application developers to learn about APIs and how to use them. Therefore, learning about APIs is a task that an application developer can perform in the Developer Portal.

E. Test an API: Application developers can test APIs from the Developer Portal. The portal provides a testing environment that allows developers to send API requests, view responses, and debug any issues that arise during testing.

F. Create an application: Application developers can create applications that consume APIs from the Developer Portal. The portal provides a set of tools and resources, such as SDKs, sample code, and developer guides, that enable developers to build applications using the APIs they consume.

Based on the above analysis, it is clear that creating an API is not an activity that an application developer can perform in the Developer Portal. Therefore, the answer to the question is C. Create an API.