Which of the following is considered a liquid asset?

Marketable securities are considered a liquid asset because they can be quickly and easily sold in the financial markets without a significant loss in value. This category includes stocks, bonds, and mutual funds that are frequently traded and have established markets. When an individual or organization needs to access cash quickly, marketable securities can be converted into cash relatively rapidly due to their demand and the availability of market exchanges.

In contrast, real estate is generally not classified as a liquid asset because selling property can take time, and market conditions can heavily influence the sale price. Similarly, private equity investments involve longer time horizons for returns and often require a complex selling process that limits their liquidity. Collectibles, while potentially valuable, also lack liquidity due to their unique nature and the specific markets for trading them, which can result in longer selling periods and variable prices. Thus, marketable securities stand out as the most liquid option among the choices given.