If you are looking for a definition, it is EXTINCT because extinct means that animal or plant no longer is living and they have died out.
If you are looking for an actual animal, a woolly mammoth is an extinct animal.
HOPE THIS HELPS!!(:
Answer:
Encourage: Correct (i think)
Explain: Correct
Justify: Correct
Playful: Incorrect
Heroic: Incorrect
Special: Incorrect