Serious irritating You Tube survey problem

I was viewing features on YouTube. At that point, while there's one stacking, in the feature screen, an overview appeared. It didn't look suspicious, as it didn't open any new tabs or anything, besides, it looked YouTube, and, as I trust YouTube, I addressed the review, and clicked the submit catch. When I did that did my feature begin playing, as well as Avast told me that a malware had been identified. I just had reliable destinations on, and I don't download anything on this PC. Will somebody let me know what this is?
