Final answer:
The best choice is that the neighbor may be able to obtain prescriptive rights for the encroachment. This is accomplished through extended, open usage of the property without permission. Other mentioned options do not directly address the encroachment remediation process.
Step-by-step explanation:
The situation described involves a potential encroachment, which is when a neighbor's building extends onto another person's property. In this scenario, the best description is that a) The neighbor may have the right to obtain prescriptive rights to allow the encroachment to remain. Prescriptive rights are acquired through the continuous and open use of property without permission over a certain period. This is similar to, but legally distinct from, adverse possession.
The other options, such as the seller causing the overhang to be removed or claiming the overhang under the right of prior appropriation, do not directly address the legal remedy for encroachment. Obtaining an easement appurtenant in the local small claims court is also not accurate, as easements are typically granted through negotiation or legal action but not necessarily in small claims court.