Which of the following may NOT be traded in secondary markets?

Mutual funds are not traded in secondary markets because they are bought and sold at the end of each trading day at their net asset value (NAV) rather than through exchanges. When an investor wants to purchase or redeem shares of a mutual fund, this transaction occurs directly with the fund company rather than on an open market, which is characteristic of secondary market trading. In contrast, rights, warrants, and exchange-traded funds (ETFs) are all kinds of securities that can be actively traded on exchanges during market hours, allowing investors to buy and sell them as desired. This distinction helps clarify the unique nature of mutual funds compared to other securities that do have secondary market trading.