Final answer:
The correct answer is mutual funds, which are professionally managed, diversified investment funds. Investors buy shares and receive returns based on the fund's performance. Exchange-traded funds (ETFs) are a similar, but distinct, investment option.
Step-by-step explanation:
Investors may invest small amounts of money over time in all-in-one funds or other kinds of investment vehicles. Among the options provided, the correct answer is mutual funds. A mutual fund is an investment fund that is professionally managed and typically diversified with assets like stocks and bonds. Investors buy shares of the mutual fund and receive returns based on the fund's overall performance.
Exchange-traded funds (ETFs) are also a popular investment option that allows investors to invest in a diversified portfolio of assets. ETFs differ from mutual funds as they are traded on stock exchanges, much like individual stocks, and can be bought and sold throughout the trading day.