Shallow understanding from people of good will is more frustrating than absolute misunderstanding from people of ill will. What is the author's purpose for including this sentence? to condemn the insincerity of his critics' advice to contrast the motivations of people in power to explain the need for mutual understanding to criticize people who treat others cruelly

Answer: A) to condemn the insincerity of his critics' advice.

Explanation: The given sentence expresses the idea that it is more frustrating people of good will with an understanding with little depth, than people of ill will that absolutely misunderstand. The author's purpose for including this sentence is to condemn the insincerity of his critics' advice, because he notices that the critics give little attention to his questions and therefore, they give very shallow advices.