Which type of estate involves lawful possession of property under an agreement for a specified period of time?

The correct answer is the type of estate known as Tenancy for Years. This form of tenancy is characterized by a lease agreement that grants lawful possession of a property for a predetermined and specified period. The duration of this tenancy can vary, but it must have a clear beginning and end date, making it distinct from other types of tenancies.

Tenancy for Years is particularly important because it establishes a legal framework for both tenants and landlords, ensuring that all parties understand their rights and responsibilities throughout the lease period. This type of agreement can also be advantageous for landlords, as it provides them with certainty regarding property occupancy and revenue for the duration of the lease.

In contrast, other forms of tenancy differ significantly in structure and terms. For instance, a tenancy at sufferance arises when a tenant continues to occupy the property after the expiration of their lease, lacking the landlord's consent, while a tenancy at will involves an agreement that can be terminated at any time by either party without a fixed term. Joint tenancy pertains to ownership rather than tenancy and typically refers to multiple owners holding equal shares and rights to the property. Therefore, the characteristics of Tenancy for Years align perfectly with the defined concept of lawful possession under a temporary agreement.