Final answer:
The use of the Azure Command Line Interface requires the Azure CLI tools and an Azure subscription. This combination enables engineers to manage Azure resources through the command line for scripting and automation purposes.
Step-by-step explanation:
To use the Azure Command Line Interface (CLI), two key things are required: Azure CLI tools and an Azure subscription. This setup enables an engineer to interact with Azure services via command line, allowing for automation and more efficient management of Azure resources.
The Azure CLI tools are a set of commands that can be executed on a command prompt or a terminal. They are designed to be idempotent, allowing repetitive commands to produce the same results, which is particularly beneficial for scripting and automation. An Azure subscription is necessary because it is the account that will be charged for the services that the engineer provisions and uses through the Azure CLI.
The correct answer to the question is thus: C) Azure CLI tools and an Azure subscription.