Which boxes (if any) were marked in line 3?

"Long-term care insurance contract. Generally, amounts received under a qualified long-term care insurance contract are excluded from your income. However, if payments are made on a per diem basis, the amount you may exclude is limited. The per diem exclusion limit must be allocated among all policyholders who own qualified long-term care insurance contracts for the same insured. See Pub. 525 and Form 8853 and its instructions for more information.
Per diem basis. This means the payments were made on any periodic basis without regard to the actual expenses incurred during the period to which the payments relate."