A listener believes Khalid and Amr jointly wrote the piece. Which reading is supported?Supplementary Practice 6: Rhetorical Dialogue, Responding to Objections and Choosing the Right ExpressionQaṣr al-qalb because Amr alone was assumedQaṣr al-taʿyīn despite a settled belief in partnershipQaṣr al-ifrādConfirmatory interrogation