The connection between pulmonary and Aortic arches in Foetus is :

Options

A. Ligamentum artriosus
B. Ductus arteriosus
C. Foramen ovale
D. All of the above

Answer

To answer the question regarding the connection between the pulmonary and aortic arches in a fetus, we can follow these steps:

### Step 1: Understand the Structures
- The pulmonary arch refers to the pulmonary artery, which carries deoxygenated blood from the heart to the lungs.
- The aortic arch refers to the aorta, which carries oxygenated blood from the heart to the rest of the body.

### Step 2: Identify the Connection in Fetal Circulation
- In fetal circulation, there is a unique structure known as the ductus arteriosus (also referred to as ductus Botalli), which plays a crucial role in connecting these two arches.

### Step 3: Analyze the Options
1. **Ligamentum Arteriosum**: This is a remnant of the ductus arteriosus that becomes a fibrous band after birth. It does not serve as a connection during fetal life.
2. **Ductus Arteriosus**: This is the correct answer. It connects the pulmonary artery to the descending aorta, allowing blood to bypass the non-functioning fetal lungs.
3. **Foramen Ovale**: This is an opening between the right and left atria, allowing blood to flow from the right atrium to the left atrium, bypassing the lungs. It is not a connection between the pulmonary and aortic arches.
4. **All of the Above**: This option is incorrect because not all the previous options are correct.

### Step 4: Conclusion
- The correct answer is **Ductus Arteriosus**, as it is the structure that connects the pulmonary and aortic arches in the fetus.

### Final Answer
- The connection between the pulmonary and aortic arches in the fetus is the **Ductus Arteriosus**.

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