Final answer:
In tenants in common, the assumption of tenancy by the surviving joint tenant(s), executor of the deceased's estate, brokerage firm, or court-appointed guardian depends on whether the deceased had a will or trust established.
Step-by-step explanation:
If an individual dies in tenants in common, the answer to who assumes tenancy of the deceased individual depends on whether or not the deceased had a will or trust established. If the deceased had a will or trust, the executor or trustee designated in the document would handle the distribution of assets, including the tenancy in the account. However, if the deceased died intestate, meaning without a will or trust, the distribution of assets would be determined by state intestacy laws. In this case, the answer would be determined based on the laws of the specific state.