**Core Concept**
Pseudo jaundice, also known as carotenemia, is a benign condition characterized by a yellowish discoloration of the skin and mucous membranes. This condition occurs due to the accumulation of carotenoids, a group of yellow-orange pigments found in certain foods and medications.

**Why the Correct Answer is Right**
The antituberculous agent associated with pseudo jaundice is rifampicin. Rifampicin is a potent bactericidal antibiotic used in the treatment of tuberculosis. It works by inhibiting DNA-dependent RNA polymerase, thereby preventing the synthesis of new RNA molecules. However, one of the side effects of rifampicin therapy is the induction of carotenoid metabolism, leading to the accumulation of carotenoids in the skin and mucous membranes, resulting in pseudo jaundice.

**Why Each Wrong Option is Incorrect**
* **Option A:** Isoniazid is another antituberculous agent used in the treatment of tuberculosis. However, it is not associated with pseudo jaundice.
* **Option B:** Ethambutol is a second-line antituberculous agent used in the treatment of drug-resistant tuberculosis. It is not associated with pseudo jaundice.
* **Option C:** Pyrazinamide is a first-line antituberculous agent used in the treatment of tuberculosis. It is not associated with pseudo jaundice.

**Clinical Pearl / High-Yield Fact**
Rifampicin-induced pseudo jaundice is a benign condition that resolves once the medication is discontinued. However, it is essential to distinguish pseudo jaundice from true jaundice, which can be a sign of a more serious underlying condition.

**Correct Answer: C. Pyrazinamide is not the correct answer, but pyrazinamide is sometimes associated with a different adverse effect (hypersensitivity and liver dysfunction).