Final answer:
The role that would use the ICD-10-CM classification system for diabetes mellitus is Coding and reimbursement.
Step-by-step explanation:
The role that would use the ICD-10-CM classification system to numerically represent the diagnosis for diabetes mellitus is Coding and reimbursement. Coding and reimbursement professionals are responsible for assigning the appropriate codes to diagnoses and procedures so that healthcare organizations can receive reimbursement from insurance companies. They use the ICD-10-CM system, which is a standardized coding system used worldwide to classify diseases. In the case of diabetes mellitus, they would assign the specific ICD-10-CM code that corresponds to the diagnosis.