Answer: a. an agreement drawn up by one person to sell land to another person
Explanation: In a legal context, a "covenant" is a conditional agreement between two parties that includes a promise or set of promises to perform or refrain from certain actions. For example, a covenant could be included in a real estate contract where the seller agrees to maintain the roof of the property for a certain period of time after the sale.
From the options you provided, option (a) is closest to the legal definition of a covenant. Option (a) is describing an agreement to sell land, which could include a covenant where the buyer promises to maintain the property in a certain way or use it for a specific purpose.