Dead brain cells or blood clots that may cause strokes
I believe the answer is c. Herpes and HIV are STD's so it's like stuck with you. :) Hope this helped!
I’m not sure if this exactly answers your question, but some eyebrows are raised at his dilemmas (morality tests) because the only people tested were 10-16 year old boys that had never been in the situations that were presented to them. Overall his dilemmas could be a reason why people question his theories. Other than this reason I am not aware of another reason why people would question his stages of moral development.
Answer: Connective Tissue
Hope that helps!! :)