Creating separate intents for each service request allows the model to better understand the specific needs of the user and provide more accurate responses. Adding specific utterances for each intent and creating entities to capture relevant information helps the model recognize and classify the user's messages correctly. Option A would not be effective as it would not allow the model to differentiate between different service requests. Option C is incorrect as using regular expressions alone may not capture all the variations and nuances of user messages. Option D is not a viable approach as creating separate intents for each specific request would result in a highly fragmented and inefficient model.