Final answer:
Upon Sue's death, as they were joint tenants with rights of survivorship, the account passes entirely to Bob, and therefore $0 from the joint account is includable in Sue's gross estate for estate tax purposes.
Step-by-step explanation:
In this case, Bob and Sue own the account as joint tenants with rights of survivorship. This means that when Sue dies, Bob automatically becomes the sole owner of the account. The inclusion in Sue's gross estate for estate tax purposes would depend on whether she made any taxable gifts during her lifetime.
If Sue made taxable gifts, the value of those gifts would be added to the account balance at the time of her death. However, if Sue did not make any taxable gifts, then the amount includable in her gross estate would be $0.
The question asks how much of the $150 in a joint account with rights of survivorship is includable in Sue's gross estate to determine the estate tax upon her death. Because Bob and Sue were joint tenants, upon Sue's death, the entirety of the account passed to Bob without being included in Sue's estate for estate tax purposes. Therefore, the correct answer is $0 ($0 is includable in Sue's gross estate).