When using Cloud Functions, which of the following is a key characteristic?

The key characteristic of Cloud Functions that makes the correct choice stand out is its ability to automatically scale based on the number of events. This serverless compute service is designed to respond to events, executing code in response to these triggers without requiring manual resource management. As the number of incoming events increases, Cloud Functions can dynamically allocate the necessary resources to handle the load, ensuring that applications remain responsive and performant.

This automatic scaling feature is particularly advantageous for applications with variable workloads, as it allows developers to focus on writing code without the overhead of provisioning or managing servers. Additionally, during periods of low demand, the resource usage and associated costs decrease, making serverless functions cost-effective by billing only for the actual usage.

In contrast, the other options present characteristics that do not align with the fundamental nature of Cloud Functions. For example, requiring a dedicated server runs counter to the serverless architecture of Cloud Functions, which abstracts away server management. Similarly, the necessity for deployment in a specific region may vary based on other factors like latency and compliance, but it is not a defining feature of Cloud Functions themselves. Lastly, a fixed billing model does not apply, as billing is typically based on the number of requests and execution time, which changes depending on usage patterns.