Final answer:
The correct code to report a nontoxic nodular goiter is a. E04.0.
Step-by-step explanation:
The correct code to report a nontoxic nodular goiter is a. E04.0. This code is found in the International Classification of Diseases, Tenth Revision (ICD-10) coding system, which is used to classify and code diagnoses in medical settings. The code E04.0 specifically refers to a nontoxic (indicating that it is not toxic and causing hyperthyroidism) nodular goiter.