Final answer:
The correct circumstance for deducting loan interest is b) points on a home equity loan incorporated into the loan.
Step-by-step explanation:
To deduct loan interest, there are specific circumstances that apply. In the given options, the correct circumstance for deducting loan interest is option (b) - Points on a home equity loan incorporated into the loan.
Interest on a home equity loan can be deducted if the loan is used to improve or renovate the home. These points can also be deducted as long as they are incorporated into the loan amount.
Therefore, the correct option for deducting loan interest is (b) - Points on a home equity loan incorporated into the loan.