Answer:
It is a run on sentence.
Explanation:
It should be "Mr. Blakely knew Seth made a bad decision. He told him so." since there's no period to differentiate between the transition, it is a run-on sentence.
It is ineffective support because it does not help prove the claim.
His claim is that they do more harm than good, but he uses a one sided study that states zoos are great for learning and species preservation.