Final answer:
The relationship where Landowner A gives Landowner B a permanent right to cross her property via a driveway is known as an easement. It is a legal right of use without the transfer of property ownership and is crucial for defining property rights.
Step-by-step explanation:
The relationship described in the question is best defined as an easement. An easement is a permanent right granted to a landowner to use a portion of another person's property for a specified purpose. In the given scenario, Landowner A has given Landowner B the right to cross her property with a driveway to access the highway. This is not a lease or a mortgage, as those involve temporary rights or financing arrangements, nor is it a deed, which is a legal document that represents ownership of property. Instead, an easement provides a right of use without transferring ownership.
Economics highlights that property rights are essential for the smooth functioning of an economy because they allow individuals and firms to own and use property as they see fit. Easements align with the concept of clearly defined property rights, as they establish legal rights of use that are enforceable in court.