For which type of investment does a bond ladder primarily aim to increase liquidity?

A bond ladder is a strategy specifically designed for bond investments. This approach involves purchasing a series of bonds with different maturities. As bonds mature at staggered intervals, the investor receives principal payments that can be reinvested or utilized for other purposes, thereby enhancing liquidity.

The primary benefit of this strategy is that it allows investors to access cash at regular intervals without having to sell a bond in a potentially unfavorable market. By having bonds mature at different times, the investor can potentially respond to changing interest rates or market conditions, maintaining greater financial flexibility.

While other types of investments, like real estate, stocks, and mutual funds, can also provide liquidity, they do not employ a laddering technique to manage cash flow as bonds do. Therefore, the focus on improving liquidity through the scheduled maturity of bonds identifies bond investments as the correct choice in this context.