The correct answer is a. A mark of social disgrace that sets the deviant apart from the rest of society.
According to the definition of the word "Stigma" it is a shameful reputation that a particular action or way of behaving has because so many people disapprove of it. An association of disgrace or public disapproval.
It all begins with an act which, since it has been disapproved by society, it will definitely have serious negative consequences towards the person who has committed such action (c.); but, the question aims to answer the meaning of the word "Stigma", and its etymology rightly refers to a mark made on the skin, from Latin Stigma; and from the Greek Stigma, a mark of a pointed instrument, among other meanings. In those days it was precisely a mark of shame or discredit. Although it is not a mark made on the skin at a present time, a person in a situation like this could carry an stigma as a lasting mark.