Kidneys are not the only organs of excretion their work is supplemented by

Options

A. Liver
B. Skin
C. Heart
D. Large intestine

Answer

### Step-by-Step Solution

1. **Understanding the Role of Kidneys**:
- Kidneys are the primary organs responsible for excretion in humans. They filter blood to remove waste products, particularly urea, and help in osmoregulation.

2. **Identifying Other Organs of Excretion**:
- While kidneys play a crucial role, other organs also contribute to the excretion process. We need to identify these organs.

3. **Analyzing the Given Options**:
- The options provided are: liver, skin, heart, and large intestine.

4. **Evaluating Each Option**:
- **Liver**: The liver converts toxic ammonia (produced from protein metabolism) into urea, which is then transported to the kidneys for excretion. Thus, the liver plays a significant role in detoxification and waste removal.
- **Skin**: The skin contains sweat glands that excrete excess salts, water, and small amounts of urea through sweat. This indicates that the skin also assists in excretion.
- **Heart**: The heart's primary function is to pump blood throughout the body. It does not directly participate in the excretion of waste products.
- **Large Intestine**: The large intestine primarily absorbs water and processes waste for elimination, but it is not a major organ of excretion in the context of metabolic waste like urea.

5. **Conclusion**:
- Based on the analysis, the organs that supplement the work of the kidneys in excretion are the liver and skin. Therefore, the correct answer is **liver and skin**.