正解:C
Microservice applications are composed of many smaller, loosely coupled, and independently deployable services, each with its own responsibility and technology stack1. One of the benefits of microservice applications in a cloud environment is that they can use auto-scaling, which is the ability to automatically adjust the amount of computing resources allocated to a service based on the current demand2. Auto-scaling can help improve the performance, availability, and cost-efficiency of microservice applications, as it allows each service to scale up or down according to its own needs, without affecting the rest of the application2. Auto-scaling can also help handle unpredictable or variable workloads, such as spikes in traffic or seasonal fluctuations2. Auto-scaling can be implemented using different cloud services, such as Google Kubernetes Engine (GKE) or Cloud Run, which provide both horizontal and vertical scaling options for microservice applications34. Reference: 1: IBM, What are Microservices?; 2: AWS, What is Auto Scaling?; 3: Google Cloud, Autoscaling Deployments; 4: Google Cloud, Scaling Cloud Run services