Answer:
Part 4 provides more evidence to support the claim. It says that based on studies, people with disabilities have been shown to be inferior to some other people. The claim states that this discrimination is "unfair and unnecessary". As said in the claim, people with disabilities are being put down for no reason and should have "the opportunity to compete on an equal basis." The fourth part shows they can't compete on an equal basis based on "census data, national polls, and other studies".
Step-by-step explanation:
Sorry I don't really have a good explanation for this, but each part usually is evidence to support the claim. Honestly, this would really be the answer if the question asked about any other part. Think about it like "main idea".
~ Also, I just took the quiz and that's what I submitted.