Benchmark indices opened on a firm note on Wednesday tracking positive start to Asian markets after concerns over US-North Korea tensions eased, even as US President Donald Trump said "all options are on the table" for the United States to respond to North Korea's recent firing of a ballistic missile. The BSE Sensex was trading 203.22 points lower at 31,591.61 while Nifty50 regained 9,850 level and was trading 65.45 points higher at 9,861.15.