The article explores how different portfolios of stocks in the Indian stock market can affect risk and return. Researchers analyzed 145 stocks from 21 sectors to create 10 portfolios with varying levels of risk and return. By using mathematical models, they found that portfolios with diverse investments had lower risk. Specifically, investing selectively in certain stocks within the portfolios led to higher returns with less risk. This study confirms that spreading investments across different stocks can help reduce overall risk in the stock market.