Question : Which opposition party played a significant role in challenging Congress dominance in northern India during the era of one-party dominance?
Option 1: Communist Party of India (Marxist)
Option 2: Bharatiya Jana Sangh
Option 3: Janata Dal
Option 4: All India Anna Dravida Munnetra Kazhagam
Correct Answer: Bharatiya Jana Sangh
Solution : The Bharatiya Jana Sangh played a significant role in challenging Congress dominance in northern India during the era of one-party dominance, particularly in states like Rajasthan, Delhi, and Madhya Pradesh.