Concept:Quru' is an Islamic legal term that relates to the waiting period observed by a woman.Explanation:In Islamic jurisprudence, Quru' refers to the menstrual periods or states of purity of a woman. It is specifically used to determine the duration of the waiting period called 'Iddah. 'Iddah, or Iddat, is the period a woman must observe after the death of her husband or after a divorce. Therefore, from the given options, Quru' is used in connection with iddah.Answer:D. iddah.