Former Indian Prime Minister Manmohan Singh (C, front) attends a congregation of senior leaders and party workers of the Indian National Congress (INC) in New Delhi, India, Dec. 23, 2019. India's main opposition party INC on Monday organised a congregation of senior leaders and party workers at "Rajghat," the memorial of Father of Nation Mahatma Gandhi, to take a pledge to uphold the country's Constitution, and oppose the new "Citizenship (Amendment) Act (CAA)." (Xinhua/Javed Dar)