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 each co-owner has an equal right to use and enjoy the entire property. This characteristic does not differentiate the two forms of ownership, as both types allow for shared access to the property.

Unity of possession is a property characteristic shared by both joint tenants and tenants in common. It means that each co-owner has the right to possess and use the whole property, rather than being limited to a specific portion. Therefore, this feature does not serve to distinguish between joint tenancy and tenancy in common.

This is the most distinguishing feature of joint tenancy. In a joint tenancy, if one owner dies, their interest automatically passes to the surviving joint tenants, whereas, in a tenancy in common, the deceased owner's interest goes to their heirs. This crucial difference makes the right of survivorship the defining characteristic of joint tenancy.