Amid tariffs and economic uncertainty, investing in stocks can be challenging, prompting cautious investors to seek reliable options. The Vanguard S&P 500 ETF (NYSEMKT: VOO) emerges as a strong investment choice, especially for retirement portfolios, due to its consistent performance and stability. The article outlines five compelling reasons why this ETF would be the preferred option if limited to a single stock or fund for long-term investment.