Which one of the following is the correct matching of the events occuring during menstrual cycle?

Options

A. Menstruation: Breakdown of myometrium & ovum not fertilized
B. Proliferative phase: Rapid regeneration of myometrium & maturation of Graffian follicle
C. Development of corpus luteum : Secretory phase & increased secretion of progesterone
D. Ovulation : LH and FSH attain peak level & sharp fall in the secretion of progesterone

Answer

To answer the question about the correct matching of events occurring during the menstrual cycle, we need to understand the key phases of the menstrual cycle and the events that occur in each phase.

### Step-by-Step Solution:

1. **Understanding the Menstrual Cycle**:
The menstrual cycle is typically divided into four main phases: the menstrual phase, the follicular phase, ovulation, and the luteal phase. Each phase has specific events associated with it.

2. **Identifying Key Events**:
- **Menstrual Phase**: Shedding of the uterine lining, resulting in menstrual bleeding.
- **Follicular Phase**: Follicle-stimulating hormone (FSH) promotes the growth of ovarian follicles.
- **Ovulation**: Release of a mature egg from the ovary.
- **Luteal Phase**: After ovulation, the ruptured follicle transforms into the corpus luteum, which secretes progesterone.

3. **Matching Events to Phases**:
- In the **luteal phase**, the corpus luteum is formed from the ruptured follicle after ovulation, and it secretes progesterone to maintain the uterine lining.
- If fertilization does not occur, the corpus luteum degenerates, leading to a decrease in progesterone and the onset of menstruation.

4. **Conclusion**:
Based on the understanding of the menstrual cycle, the correct matching of events is:
- **Development of corpus luteum in the luteal phase and increase in progesterone levels**.

### Final Answer:
The correct matching of the events occurring during the menstrual cycle is the development of the corpus luteum in the luteal phase and the increase in progesterone.