Mumbai, April 28 -- Benchmark stock indices Sensex and Nifty rebounded nearly 1% on Monday, snapping the three-day falling streak following a rally in Reliance Industries and Sun Pharma and positive global trends. The 30-share BSE Sensex jumped 639.42 points or 0.83% to settle at 77,303.63. During the day, it surged 755.83 points or 0.98% to 77,420.04. The 50-share NSE Nifty climbed 194.75 points or 0.81% to close at 24,092.70. Among the 30-Sensex firms, Sun Pharma jumped 7% after it announced the acquisition of US-based Organon & Co in an all-cash deal at an enterprise valuation of $11.75 billion, one of the largest overseas buyouts by Indian firms. Reliance Industries jumped 2.88%. Adani Ports, Tech Mahindra, Mahindra & Mahindra, NTPC, HCL Tech and Tata Consultancy Services were also among the major gainers. Axis Bank, Bharat Electronics, Trent and ICICI Bank were among the laggards from the blue-chip pack. "The upmove was primarily driven by a rebound in beaten-down heavyweights across sectors, particularly Reliance, along with positive developments such as a sharp rally in pharma majors following global acquisition news. Additionally, optimism around potential progress in US-Iran negotiations supported global sentiment, even as crude oil prices remained elevated," Ajit Mishra - SVP, Research, Religare Broking Ltd, said. The BSE SmallCap Select index jumped 2% and MidCap Select index climbed 1.35%. All sectoral indices ended higher. Utilities surged the most by 2.50%, followed by Healthcare (2.43%), Focused IT (2.41%), Realty (2.35%), IT (2.20%), Power (2.05%) and Services (1.92%). A total of 3,075 stocks advanced, while 1,288 declined and 193 remained unchanged on the BSE. Among Asian markets, South Korea's benchmark Kospi, Japan's Nikkei 225 index, and Shanghai's SSE Composite index ended higher, while Hong Kong's Hang Seng index ended lower. Markets in Europe were trading in positive territory. US markets ended mostly higher on Friday. "A key catalyst behind today's strength was improving global sentiment, particularly reports of a potential de-escalation between the US and Iran around the Strait of Hormuz. This development eased supply disruptions and supported global risk appetite, helping domestic markets stabilise and rise," Hariprasad K, Research Analyst and Founder, Livelong Wealth, said. Sectoral participation played an important role in sustaining the rally, he noted. "The pharmaceutical space saw strong traction, led by a sharp surge in Sun Pharmaceutical Industries following its announcement of a large acquisition deal involving Organon. The IT sector also witnessed a notable rebound after recent underperformance," Hariprasad added. Brent crude, the global oil benchmark, traded 2.53% higher at $107.9 per barrel. "Indian equities began the week on a positive note, supported by improved sentiment amid renewed expectations of near-term de-escalation in the Middle East. Gains were widespread, with all major sectoral indices ending in positive territory. Overall, markets demonstrated resilience but remain highly sensitive to geopolitical developments," Ponmudi R, chief executive officer of Enrich Money, an online trading and wealth tech firm, said. Foreign Institutional Investors (FIIs) offloaded equities worth Rs.8,827.87 crore on Friday, according to exchange data....