The highest area in percentage of the Banganga river basin lies in the ______…

The correct district is Bharatpur.

The Banganga river basin has a total catchment area of about 8,878 sq km, spread across the north-eastern districts of Rajasthan (chiefly Jaipur, Dausa, Alwar, Bharatpur, Deeg, Karauli, Sawai Madhopur and Sikar). Among these, Bharatpur district covers the largest share of the basin — about 2,746 sq km, which is the highest percentage of the basin's total area. Alwar (~2,332 sq km) and Dausa (~2,131 sq km) follow. Although the Banganga rises in the Aravalli hills near Bairath in Jaipur district, its basin spreads out and occupies the greatest proportion of land in Bharatpur.