Which option gives an investor the right to sell shares?

A put option grants an investor the right to sell shares at a predetermined price within a specified time frame. This financial instrument is often used by investors who anticipate that the price of the underlying asset will decline. By holding a put option, the investor can sell the shares at the strike price even if the market price falls below it, thus providing a form of insurance against a decrease in value.

In contrast, the other options do not provide the right to sell shares. A convertible option refers to a security that can be converted into another form, often shares, but does not involve the right to sell. A call option gives the holder the right to buy shares, not sell them. An equity option is a broader term that encompasses both call and put options related to stock. Thus, the specific characteristic of the put option that allows for the sale of shares distinguishes it as the correct choice.