Carmen, westbrook, and ashton are concurrent owners of a large commercial building. ashton executes a will that leaves all his property to his son in the event of his death. but after ashton's death, his ownership interest in the building was acquired by the remaining two tenants of the building.
which of the following kinds of concurrent ownership would allow such a passage of title?

a) a tenancy by entirety
b) a community property
c) a joint tenancy
d) a tenancy in common