Which organ in the excretory system expels the urine out from the body?

Options

A. Kidneys
B. Ureters
C. Urinary bladder
D. Urethra

Explanation

**Step-by-Step Solution:**

1. **Understanding the Excretory System**: The excretory system is responsible for the removal of waste products from the body, primarily in the form of urine.

2. **Identifying the Organs Involved**: The main organs involved in the excretory system include:
- Kidneys: Filter blood to produce urine.
- Ureters: Transport urine from the kidneys to the bladder.
- Urinary Bladder: Stores urine until it is ready to be expelled.
- Urethra: The tube through which urine is expelled from the body.

3. **Function of Each Organ**:
- **Kidneys**: They filter waste from the blood and produce urine.
- **Ureters**: They carry urine from the kidneys to the urinary bladder.
- **Urinary Bladder**: It stores urine until it is full and ready to be expelled.
- **Urethra**: This is the final pathway through which urine exits the body.

4. **Determining the Correct Answer**: The question asks which organ expels urine out of the body. Based on the functions:
- The kidneys produce urine but do not expel it.
- The ureters transport urine but do not expel it.
- The urinary bladder stores urine but does not expel it.
- The urethra is the organ that expels urine from the body.

5. **Conclusion**: Therefore, the correct answer is the **urethra**.

**Final Answer**: The organ in the excretory system that expels urine out from the body is the **urethra**.

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