All the 16 vital sectors traded lower while broader small-caps and mid-caps dropped about 0.6% each. (Express Photo/File)Stocks opened lower on Monday after renewed tensions in the Middle East with Iran shutting the crucial Strait of Hormuz, pushing the crude oil prices higher.At 9.15 am, The benchmark Nifty 50 plummeted 0.69% to 24,039.4, while the BSE Sensex shed 0.78% to 76,963.35.All the 16 vital sectors traded lower while broader small-caps and mid-caps dropped about 0.6% each.The US and Iranian forces exchanged heavy missile and drone assaults, with Tehran targeting US facilities in states across the Gulf on Sunday and saying it had again closed the vital Strait of Hormuz.