Final answer:
The year-six Section 1231 gain of UNA Corporation can be characterized as $80,000 ordinary income.
Step-by-step explanation:
The year-six Section 1231 gain of UNA Corporation can best be characterized as option 3) 80,000 ordinary income. A Section 1231 gain is treated as ordinary income for tax purposes. Therefore, the gain of $80,000 in year six would be considered ordinary income for UNA Corporation.