The question is asking us to mention the name of the organ shed off during the menstrual cycle. Specifically, it says, once a female reaches puberty, the uterus sheds an unfertilized egg along with the.... uterine wall - that is the correct answer. The Uterine wall is how the female body prepares for pregnancies, and it is there to protect and nurture the child - so if the pregnancy does not occur, it is shed.
