Answer:
The phrase that provides the best clue to the meaning of the word habitable is "TRAPPIST-1h is located beyond the outer edge of the habitable zone, and is likely too cold for life as we know it."
Explanation:
This phrase provides the best clue because it is saying that it's not habitable, and that it's likely too cold for life. Habitable means that it is suitable for any life form. Likely too cold for life, can also be said as, "Not habitable".