The first Indian appointed as the chief economist of the World Bank in September, 2012 is

The answer is C) Kaushik Basu. In September 2012 he took over as Chief Economist and Senior Vice President for Development Economics at the World Bank, becoming the first Indian to hold that post. Before moving to Washington, he had served as Chief Economic Adviser to the Government of India from 2009 to 2012, which is why his appointment was widely noted in the Indian press.

Why the others are wrong:

• Amartya Sen is a Nobel laureate in economics (1998) and a Harvard academic, but he never held a World Bank post.
• Jagdish Bhagwati is a leading trade economist at Columbia, known for his work on liberalisation. He has no World Bank appointment in this role.
• Vijay Kelkar chaired the 13th Finance Commission and has worked on fiscal federalism, but he is not associated with the World Bank's chief economist position.

The core concept here is the World Bank's internal economic leadership and its role in development policy. For Mains, the link is to India's economic advisory machinery and how Indian economists shape global development thinking, including on poverty, inequality and fiscal policy.

Trap: candidates often pick Amartya Sen because of his fame, or confuse the World Bank post with an IMF role. Check the exact institution and designation in the question.