Mumbai, Oct. 12 -- The key equity benchmarks ended lower on Monday, extending their cautious trend as investors awaited India's September inflation data. Persistent concerns over elevated crude oil prices and a sharp rise in Indian bond yields weighed on sentiment. Although oil prices retreated amid hopes of easing geopolitical tensions between Russia and Ukraine, Brent crude remained above $105 a barrel, keeping concerns over imported inflation and pressure on the rupee in focus. Investors also assessed the implications of the Reserve Bank of India's recent tightening measures for liquidity and borrowing costs. The Nifty settled below the 22,400 mark, while sectoral performance remained mixed, with auto and realty shares advancing even a...