Vasa recta is the continuation of

Options

A. afferent arteriole
B. efferent arteriole
C. renal vein
D. renal nerve

Answer

**Step-by-Step Solution:**

1. **Understanding Vasa Recta**: Vasa recta are specialized blood vessels that play a crucial role in the kidney's function, particularly in the medullary region.

2. **Identifying the Source**: To determine what the vasa recta is a continuation of, we need to look at the blood vessels associated with the nephron, specifically the afferent and efferent arterioles.

3. **Differentiating Afferent and Efferent Arterioles**:
- The **afferent arteriole** carries blood into the glomerulus where filtration occurs.
- The **efferent arteriole** carries blood away from the glomerulus.

4. **Tracing the Efferent Arteriole**: After blood is filtered in the glomerulus, it exits through the efferent arteriole. This vessel then continues into the medullary region of the kidney.

5. **Formation of Vasa Recta**: The efferent arterioles branch into the vasa recta as they descend into the medulla. Thus, the vasa recta is a continuation of the efferent arterioles.

6. **Conclusion**: Based on this understanding, the correct answer to the question "Vasa recta is the continuation of" is the **efferent arteriole**.

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