**Core Concept**
The management of tuberculosis (TB) in patients with hepatic dysfunction requires careful consideration of antitubercular drugs that are safe to use in the presence of liver impairment. The liver plays a crucial role in the metabolism and excretion of many antitubercular drugs, and some drugs are more susceptible to liver toxicity than others.

**Why the Correct Answer is Right**
Isoniazid (INH) is generally considered safe to use in patients with mild to moderate hepatic dysfunction. INH is primarily metabolized by the liver, but its metabolism is not significantly affected by liver impairment. However, INH can cause hepatotoxicity, and patients with pre-existing liver disease should be closely monitored for signs of liver damage. Rifampicin, on the other hand, is a potent enzyme inducer that can increase the metabolism of other drugs, including INH, and may exacerbate liver toxicity.

**Why Each Wrong Option is Incorrect**
**Option A:** Pyrazinamide is contraindicated in patients with hepatic dysfunction due to its high risk of hepatotoxicity, particularly when used in combination with INH.
**Option B:** Ethambutol is generally safe to use in patients with normal renal function, but its use in patients with hepatic dysfunction has not been extensively studied, and it may accumulate to toxic levels in the presence of liver impairment.
**Option C:** Streptomycin is an aminoglycoside antibiotic that is primarily excreted by the kidneys, and its use in patients with hepatic dysfunction is not typically a concern.

**Clinical Pearl / High-Yield Fact**
When managing TB in patients with hepatic dysfunction, it is essential to carefully weigh the benefits and risks of each antitubercular drug and to closely monitor patients for signs of liver damage.

**Correct Answer:** C.