Someone who invests in the Vanguard Index 500 mutual fund could most accurately be described as using which approach?

A) Active management
B) Arbitrage
C) Fundamental analysis
D) Passive investment

Investing in a Vanguard Index 500 mutual fund follows a passive investment approach, where investors aim to replicate market returns by buying a diversified portfolio with low fees and a long-term investment horizon. Vanguard Index 500 mutual fund tracks the performance of the S&P 500 index, which comprises of 500 large-cap U.S. stocks, offering broad market exposure.