Concept:The question tests knowledge of the tribal origin of Halimah, the foster mother of Prophet Muhammad (S.A.W.).Explanation:Halimah al-Sa'diyah was the wet nurse of Prophet Muhammad (S.A.W.).She belonged to the tribe of Banu Sa'd, specifically the Banu Sa'd ibn Bakr.This tribe was a subdivision of the larger Hawazin tribe in Arabia.Hence, Halimah did not belong to the Quraysh, Khuza'ah, or Mustaliq tribes.Answer:B. Sa'ad