**Core Concept**
Sphenoidal wing meningiomas are a type of intracranial tumor that originates from the meninges, the protective membranes surrounding the brain and spinal cord. These tumors can grow and extend into adjacent structures, including the orbit.

**Why the Correct Answer is Right**
Sphenoidal wing meningiomas are known to be locally aggressive and can extend into the orbit through the orbital fissures. This is because they originate from the sphenoidal wing, a region of the meninges that is in close proximity to the orbit. The tumor's growth into the orbit can cause a range of symptoms, including proptosis (bulging of the eye), visual disturbances, and pain. The extension of a sphenoidal wing meningioma into the orbit is a well-documented clinical phenomenon.

**Why Each Wrong Option is Incorrect**
**Option A:** Astrocytomas are a type of glioma that arise from astrocytes, a type of glial cell in the brain. While they can be malignant and invasive, they are not typically associated with orbital extension.

**Option B:** Pituitary adenomas are benign tumors that arise from the pituitary gland, which is located at the base of the brain. They can cause a range of endocrine disorders, but orbital extension is not a typical feature.

**Option C:** Craniopharyngiomas are benign tumors that arise from the pituitary stalk and can cause visual disturbances and endocrine disorders. However, they are not typically associated with orbital extension.

**Clinical Pearl / High-Yield Fact**
The key to diagnosing sphenoidal wing meningioma is to recognize the characteristic "sphenoid wing sign" on CT or MRI scans, which shows erosion of the sphenoid bone and extension of the tumor into the orbit.

**✓ Correct Answer:** D. Sphenoidal wing meningioma