Final answer:
An encroachment occurs when a portion of one person's property is built on another person's land without permission.
Step-by-step explanation:
The correct answer is B. Encroachment. An encroachment occurs when a portion of one person's property is built on another person's land without permission. In this scenario, Joe's building was inadvertently built on Ginny's land, making it an encroachment. Encroachments can lead to legal disputes and may require resolution through negotiations, legal action, or agreements such as easements.