This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Mycobacterial Diseases (TB, Leprosy and MAC), Subject name: Pharmacology
A 9-year-old boy diagnosed as uncomplicated pulmonary tuberculosis. He is put on isoniazid, rifampin, and ethambutol at home after initial treatment given at hospital. Which is accurate statement for this scenario? 
Select and explain. 
A. His 3-year-old sibling should receive INH prophylaxis, B. A baseline test of auditory function test is essential before drug treatment is initiated, C. Polyahralgia is a potential adverse effect of the drugs the boy is taking, D. His mother, who takes care of him, does not need INH prophylaxis
A: His 3-year-old sibling should receive INH prophylaxis
Answer: A: His 3-year-old sibling should receive INH prophylaxis 
Explanation: Prophylaxis with INH is always advisable for family members and close contacts in active cases. None of the drugs prescribed is associated with nephrotoxicity. Polyahralgia is a side effect of pyrazinamide that's not given in this case. Routine LFTs should be done in younger patients if INH plus rifampin given in higher doses. Ocular Function test should be done before staing ethambutol.