Final answer:
An appurtenant easement requires two adjacent parcels and one owner. It allows the dominant property owner to use a specific right over the neighboring property.
Step-by-step explanation:
For an appurtenant easement to exist, two adjacent parcels and one owner must exist. An appurtenant easement is an easement that benefits a dominant or neighboring property. It allows the owner of the dominant property to make use of a specific right over the neighboring property. The owner of the neighboring property, also known as the servient property, has the obligation to allow the use of the easement by the dominant property owner.
For example, if Parcel A is adjacent to Parcel B and owned by the same person, an appurtenant easement can be created to allow Parcel A to access a road that runs through Parcel B. This would provide an easement for Parcel A, which benefits from the right of access, and Parcel B would have the obligation to allow access through the easement.
The other options listed in the question are not necessary for the existence of an appurtenant easement. Long-time unauthorized usage may create an easement by prescription, but this is a different type of easement and not specifically related to appurtenant easements. Landlocked property that requires passage to the street may also create an easement, but again, this is not specific to appurtenant easements.