Task: Instance Class Understanding (ontology: Sciences/Computer_Science)

Which of the following classes does 'G2 (Fuhrman)' belong to as one valid explicit type? Context: A histologic grade according to the Fuhrman Nuclear Grading System indicating that nuclei are slightly irregular, approximately 15um and nucleoli are evident.

A. pathologic distant metastases stage for kidney according to AJCC 7th edition
B. International Federation of Gynecology and Obstetrics ovarian cancer stage value specification
C. histologic grade according to AJCC 7th edition
D. histologic grade according to the Fuhrman Nuclear Grading System

Answer: histologic grade according to the Fuhrman Nuclear Grading System