What type of lease agreement can be terminated by either the landlord or tenant upon giving notice?

The correct answer is the estate at will, as it is characterized by its flexibility and lack of a fixed term. In an estate at will arrangement, either the landlord or the tenant has the right to terminate the lease at any time, provided they give proper notice to the other party. This arrangement signifies a degree of mutual agreement to terminate the lease without the constraints of a set duration, making it ideal for short-term and informal rental situations.

On the other hand, periodic tenancies typically operate on a rental cycle, such as week-to-week or month-to-month. While these can also be terminated by either party, they generally require advance notice that aligns with the rental period. Tenancy by the entirety refers to a form of joint ownership for married couples and isn't related to lease agreements. A life estate is a property interest that lasts for the lifetime of a specific individual and does not pertain to lease agreements or the rights of tenants and landlords in the way that estate at will does.