If the egg is not fertilized then lining of which of the following breaks and come out as blood ?

Options

A. Cervix
B. Oviduct
C. Vagina
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Menstrual Cycle:**
- The menstrual cycle involves the release of an egg (ovulation) from the ovary and the preparation of the uterus for potential pregnancy.

2. **Role of the Uterus:**
- After ovulation, the uterus prepares itself to receive a fertilized egg. This preparation involves the thickening of the endometrial lining, which is the inner lining of the uterus.

3. **What Happens if the Egg is Not Fertilized:**
- If the egg released during ovulation is not fertilized by sperm, the body recognizes that pregnancy has not occurred.

4. **Shedding of the Endometrial Lining:**
- In response to the lack of fertilization, the thickened endometrial lining breaks down and is shed from the body.

5. **Menstrual Flow:**
- This shedding of the endometrial lining occurs during menstruation, resulting in the discharge of blood and tissue from the uterus through the vagina.

6. **Conclusion:**
- Therefore, if the egg is not fertilized, it is the lining of the uterus (specifically the endometrium) that breaks down and comes out as blood.

**Final Answer:**
The lining that breaks and comes out as blood is the lining of the uterus (endometrium).

---