**Core Concept**
Tetracycline, a broad-spectrum antibiotic, can cause pseudotumor cerebri (intracranial hypertension) as a rare but serious side effect. This condition is characterized by increased intracranial pressure without any obvious cause, often accompanied by headache, vision changes, and papilledema.

**Why the Correct Answer is Right**
Tetracycline, particularly the older generations, have been associated with pseudotumor cerebri due to their ability to alter the blood-brain barrier permeability. This increased permeability allows for the accumulation of cerebrospinal fluid (CSF), leading to elevated intracranial pressure. The exact mechanism is not fully understood, but it is thought to involve the antibiotic's effect on the CSF dynamics and the blood-brain barrier.

**Why Each Wrong Option is Incorrect**
**Option A:** Sparfloxacin, a fluoroquinolone antibiotic, does not have a well-documented association with pseudotumor cerebri. Its side effect profile is primarily related to phototoxicity, QT interval prolongation, and tendinopathy.
**Option C:** Gentamicin, an aminoglycoside antibiotic, is primarily known for its ototoxicity and nephrotoxicity. While gentamicin can cause various side effects, pseudotumor cerebri is not commonly associated with its use.
**Option D:** Clofazimine, an antimycobacterial agent used in the treatment of leprosy, is not typically linked to pseudotumor cerebri. Its side effect profile includes skin discoloration, gastrointestinal issues, and hematologic effects.

**Clinical Pearl / High-Yield Fact**
It is essential to be aware of the rare but serious side effects of medications, including pseudotumor cerebri caused by tetracycline. Monitoring patients for signs of increased intracranial pressure, such as headache and vision changes, is crucial when prescribing these antibiotics.

✓ Correct Answer: B. Tetracycline