This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
Treatment of choice for sputum positive pulmonary tuberculosis detected in 1st trimester of preg ancy- 
Select and explain. 
A. Defer till second trimester, B. Start cat. I immediately, C. Start cat. II immediately, D. Start cat. III immediately
B: Start cat. I immediately
Answer: B: Start cat. I immediately 
Explanation: None