Shelly buys Mark’s house, which is still in an option period with Monique.

An option contract gives the optionee (Monique) the exclusive right to purchase a property within a specified period and under specific terms, but not the obligation to do so.

When properly executed and supported by consideration (the option fee), the option is a binding contract on the property owner (Mark) and any subsequent owners who take title with constructive notice of the existing option.

Therefore, when Monique exercises her valid option within the option period, Shelly must honor it—the property must be sold to Monique under the agreed terms.