I don’t understand this Sociology question and need help to study.

What would you identify as the most obvious problem with how Salk went about obtaining informed consent? (Think and answer in terms of the components for informed consent reviewed in lecture.) Be sure you say enough to convince me that you made the “right” selection. Taking a broader view, which “validity” issue loomed largest in SAlk’s research for finding a polio vaccine? (Again think about my earlier lecture on the 3 major validity issues and select and defend one that strikes you as most germane to the excerpt you read.)