**Core Concept**
Tubercular meningitis is a form of bacterial meningitis caused by Mycobacterium tuberculosis that affects the meninges, leading to inflammation and potential complications. The condition can result in various neurological and systemic manifestations due to the involvement of the central nervous system.

**Why the Correct Answer is Right**
Cortical venous thrombosis is not commonly associated with tubercular meningitis. This is because the typical cerebral vasculature affected in tubercular meningitis is the small and medium-sized arteries, such as the lenticulostriate arteries, rather than the cortical veins. The inflammation and vasculitis in tubercular meningitis primarily involve the arterial supply to the brain, leading to complications like cerebral artery thrombosis and infarction.

**Why Each Wrong Option is Incorrect**
* **Option A:** Hydrocephalus is a well-documented complication of tubercular meningitis. The inflammation and scarring of the meninges can lead to obstruction of the cerebrospinal fluid pathways, resulting in hydrocephalus.
* **Option C:** Cerebral artery thrombosis is a recognized complication of tubercular meningitis. The vasculitis and inflammation in the small and medium-sized arteries can lead to thrombosis and subsequent infarction.
* **Option D:** Cranial nerve palsy can occur in tubercular meningitis due to the involvement of the cranial nerves in the base of the brain. The inflammation and vasculitis can lead to damage to the cranial nerves, resulting in palsy.

**Clinical Pearl / High-Yield Fact**
It is essential to recognize that tubercular meningitis can present with a wide range of neurological symptoms, including headache, fever, and altered mental status. The condition can also lead to complications like hydrocephalus, cerebral artery thrombosis, and cranial nerve palsy. A high index of suspicion is necessary for early diagnosis and treatment.

**✓ Correct Answer: B. Cortical venous thrombosis**