Explanation
Apache FreeMarker is a templating language used to create dynamic webpages. It is designed to separate the configuration and data states, allowing the template to have a consistent look and feel across all webpages.
FreeMarker allows the template to instantiate the data, allowing the template to be reused in different contexts.
It does not allow communication between NSP applications or transport YANG data.

Explanation
According to the Mistral Workflow Language (v2) website1, a workflow definition consists of several attributes that define its properties and behavior. The common workflow attributes are: name, description, type, input, output and vars1.

Explanation
Kafka is a distributed messaging system that is open-source and can be used to send real-time notifications.
However, it has more than four components, such as brokers, partitions, replicas, consumer groups and zookeeper.

Explanation
The correct answer is Fault Management API. The Fault Management API can be used to identify the root cause(s) of issues in the network, such as hardware or software faults, configuration errors, and other problems. It provides a unified interface to receive and analyze fault information from multiple network elements.
The API that can identify the root cause(s) of issues in the network is the Fault Management API. This API allows network operators to monitor network faults and events in real-time, and diagnose and resolve issues quickly and efficiently. It provides information about the root cause(s) of the fault and the affected network elements, as well as enabling automated fault handling and resolution.

Explanation
The HTTP methods that are supported by REST/RESTCONF are:
* GET: Used to retrieve a representation of a resource.
* PUT: Used to replace a resource or create it if it does not exist.
* DELETE: Used to delete a resource.
* PATCH: Used to apply a partial update to a resource.
The HTTP method ADD is not a standard HTTP method and is not supported by REST/RESTCONF.