Most abundant elements in the living cells are

Options

A. C, O, N and P
B. C, H, O and Ca
C. C, H, O and N
D. C, H, Mg and N

Answer

**Step-by-Step Text Solution:**

1. **Identify the Question**: The question asks for the most abundant elements in living cells.

2. **Consider the Options**: The options provided are:
- Option 1: Carbon, Oxygen, Nitrogen, and Phosphorus
- Option 2: Carbon, Hydrogen, Oxygen, and Calcium
- Option 3: Calcium, Hydrogen, Oxygen, and Nitrogen
- Option 4: Carbon, Hydrogen, Magnesium, and Nitrogen

3. **Recall the Common Elements in Living Cells**: The most common elements found in living organisms are:
- Carbon (C)
- Hydrogen (H)
- Oxygen (O)
- Nitrogen (N)

4. **Analyze the Options**:
- Option 1 includes Phosphorus, which is important but not as abundant as the four main elements.
- Option 2 includes Calcium, which is less abundant in comparison to the main four.
- Option 3 includes Calcium and does not include Carbon.
- Option 4 includes Magnesium, which is also less abundant compared to the main four.

5. **Select the Correct Answer**: The only option that includes all four of the most abundant elements (C, H, O, N) is:
- **Option 2: Carbon, Hydrogen, Oxygen, and Nitrogen**.

6. **Conclusion**: Therefore, the most abundant elements in living cells are Carbon, Hydrogen, Oxygen, and Nitrogen.

**Final Answer**: Option 2: Carbon, Hydrogen, Oxygen, and Nitrogen.

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