The feature that most distinguishes a joint tenancy from a tenancy in common is

Both joint tenancy and tenancy in common involve undivided interests in the property, meaning that all tenants share the same interest collectively rather than having specific portions of the property. This characteristic does not serve as a differentiator between the two forms of ownership since both arrangements provide for shared ownership.

Unity of possession refers to the concept that all tenants have equal rights to occupy and use the entire property. This principle applies equally to both joint tenancy and tenancy in common, making it another feature that does not distinguish between the two ownership structures.

The right of survivorship is specific to joint tenancies and means that when one owner dies, their interest automatically passes to the surviving joint tenants. This critical feature sets joint tenancy apart from tenancy in common, where a deceased owner's share is passed according to their will or state law, rather than to the other co-owners.