The site is run by Quackwatch, and the National Council Against Health Fraud. Don't you think that if they had proof positive that chiropractic was utterly ineffective, the site would be called "no more chiropractors" instead of "the reluctant sceptic's guide to getting the best of it"?
The majority of the material I have looked at there repeatedly states that the site is intended to raise awareness of the high percentage of chiropractors engaged in dubious practices, which is commentary on the academic and regulatory shortcomings of the profession, and not the actual practice itself.
Can you say "bad data sample"?
You haven't earned the right to decry it as false. You have no "proof" that it has no effects. You haven't done any studies, research, experimentation or sampling. You have no results, hypothesis, or conclusions.
All you've done is decided to take a side, slapped a web site down and said "there we go chaps, find some stuff in there that makes my opinion look scientific, then agree with me in this poll".
Now that is quackery.
Furthermore, since your poll question indicates specifically that you want peoples' opinions and not any sort of actual evidence, you need to give an out clause that acknowledges the scope of opinion alone can't sufficiently address the issue. So option 4 stays.
"You didn't read anything..."
Irrelevant. My issue is with your approach, not the material.
You might as well be saying "I read OJ's testimony and he said he didn't do it, so I think he didn't do it. I'm going to make a poll now, and get other people to read it and vote."