Subjects with a serious illness may be at risk for exploitation since they may be desperate for a possible cure. This is an example ofA. Deferential vulnerabilityB. Therapeutic misconceptionC. Medical VulnerabilityD. Economic vulnerability

Medical vulnerability is defined as the capability persisted by an ill, sick or injured individual who is under medical assistance grasp risk-oriented situation. Due to the weakness and impairment present in the person from already being sick makes them vulnerable towards further exploitation.

Other options are incorrect because deferential vulnerability makes a junior person vulnerable in the case when they feel obligated.Economic vulnerability is exposure caused to economic rate for being at risky situation.

Therapeutic misconception is the misunderstanding of as person involved in therapeutic medical study thinking that he is receiving a therapy.thus, the correct option is option(C).