Which service is used to enhance security in Kubernetes with network policies?

Kubernetes Engine is the correct service used to enhance security in Kubernetes through the implementation of network policies. In Kubernetes, network policies are a critical feature that allows you to control the communication between pods and services within the cluster. By defining network policies, you can restrict traffic at the IP address or port level, thereby enhancing the security posture of your applications running in Kubernetes.

Kubernetes Engine provides the necessary infrastructure for deploying, managing, and scaling containerized applications. It includes native support for network policies, enabling users to specify which pods can communicate with each other and which cannot. This is particularly important in a microservices architecture where different components may have varying security requirements.

Other services like Cloud Functions, BigQuery, and Cloud Storage do not pertain to Kubernetes' networking capabilities or network security configurations. They serve different purposes, such as serverless computing, data analytics, and object storage, and do not provide the same level of control over pod-to-pod communication that network policies in Kubernetes Engine do. Thus, Kubernetes Engine is integral for enforcing the desired security policies in a Kubernetes environment.