The image being shown here is the base of  a cranium of patient who has a confirmed diagnosis meningeal tumor with bone invasion. Which of the following sentence is most appropriate regarding the meningeal tumor? Answer

A.  The tumor is a WHO grade I meningioma.

B.  The tumor is a WHO grade II meningioma because of bone invasion.

C.  The tumor is a WHO grade II or III meningioma because of bone invasion.

D.  The tumor is a WHO grade III meningioma because the tumor is invading into the adjacent bone.

E.  The WHO grade of the tumor cannot be determined because bone invasion is not a diagnostic criteria for WHO grading of meningioma.