INSULT means to speak to or treat with disrespect or scornful abuse.
Option A is the correct answer because 'to humiliate' means to make someone feel ashamed or lose respect for himself or herself, hence it is the correct answer.
Option B is incorrect because 'credulity' means a tendency to be too ready to believe that something is real or true, hence it is different from 'insult'.
Option C is incorrect because 'degradation' means the situationin which people are made to feel they have no value , which is not directly an insult, hence it is incorrect.
Option D is incorrect because 'honour' means high respect or great esteem hence it is incorrect, as it is the opposite of 'insult'.