The reason that supports the author's point that Togo overcame obstacles to become a sled dog is:
Togo's small size made his owner think that he would never be a good sled dog.
<h3>What obstacle did Togo face?</h3>
Togo faced the obstacle of not being trusted because of his miniature size.
He overcame the challenge of being underestimated by leading the team out of danger. Togo gained the admiration of all after he successfully overcame his weakness.