Sorry, i need to correct my previous answer. As far as i knows Language Modeling is the service that is able to understand user input and generate actions consequently. I queried again chatgpt about this, here is the answer:
"You're right, I apologize for the confusion. In the case where you need to create a chatbot that performs various actions based on user input, the most appropriate type of NLP to use is language modeling (D). Language modeling refers to the ability to understand the meaning and intentions of the user through natural language processing. With language modeling, the chatbot can analyze user input, recognize order requests, retrieve support documentation, and provide order status updates, initiating the corresponding actions based on the information extracted from the textual input."