Benchmark Sensex and Nifty advanced in a volatile trade on Monday, driven by heavy buying in index major Reliance Industries and unabated foreign fund inflows.Bouncing back from Friday’s decline, the 30-share BSE Sensex gained 63.72 points or 0.10 per cent to settle at 65,344.17. During the day, it climbed 353.04 points or 0.54 per cent to 65,633.49.