Certain carbonates and phosphates are removed by

Options

A. skin
B. liver
C. kidneys
D. None of these

Answer

**Step-by-Step Solution:**

1. **Identify the Organs Involved in Excretion**: Begin by recognizing the main organs responsible for excretion in the human body, which include the kidneys, liver, and skin.

2. **Understand the Role of the Kidneys**: The kidneys play a crucial role in filtering blood and removing waste products. They are responsible for regulating various substances, including electrolytes, water, and waste products.

3. **Focus on Carbonates and Phosphates**: The question specifically asks about the removal of certain carbonates and phosphates. It is important to know that the kidneys are involved in the excretion of these substances.

4. **Explain the Excretion Process**: The kidneys filter out excess phosphates from the blood and excrete them in urine. They also help in regulating calcium levels, which can be associated with carbonate levels in the body.

5. **Consider Kidney Dysfunction**: If the kidneys are not functioning properly, it can lead to the accumulation of waste products, including carbonates and phosphates, which can result in the formation of kidney stones.

6. **Conclude with the Correct Answer**: Based on the above points, the correct answer to the question is that certain carbonates and phosphates are removed by the kidneys.

**Final Answer**: Certain carbonates and phosphates are removed by the kidneys.

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