Oxygenated blood enters the kidney through the :

Options

A. hilus artery
B. renal portal system
C. renal arteries
D. renal vein

Explanation

To determine how oxygenated blood enters the kidney, we can follow these steps:

### Step 1: Identify the blood vessels involved
The question asks about the entry of oxygenated blood into the kidney. The main blood vessels to consider are the renal arteries, renal veins, and any other relevant structures.

### Step 2: Understand the function of renal arteries
The renal arteries are responsible for carrying oxygenated blood from the heart to the kidneys. Each kidney receives blood from the right and left renal arteries.

### Step 3: Eliminate incorrect options
- **Highless artery**: This is not a recognized term in human anatomy related to kidney blood supply.
- **Renal portal system**: This system is involved in the venous return from the kidneys, not in the entry of oxygenated blood.
- **Renal vein**: This carries deoxygenated blood away from the kidneys, not towards them.

### Step 4: Confirm the correct answer
Since the renal arteries are the vessels that carry oxygenated blood to the kidneys, we conclude that the oxygenated blood enters the kidney through the renal arteries.

### Final Answer
Oxygenated blood enters the kidney through the **renal arteries** (Option C).

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