Most of the mass of organic material of a plant comes from

Options

A. water
B. atmospheric oxygen
C. carbon dioxide
D. nitrogen

Answer

**Step-by-Step Solution:**

1. **Understanding Plant Mass Composition**: The question asks about the source of the mass of organic material in plants. It is important to recognize that the majority of a plant's mass is derived from organic compounds, primarily carbon-based compounds.

2. **Identifying the Main Element**: The primary element that constitutes the mass of organic material in plants is carbon. This is because organic materials, such as carbohydrates, proteins, and fats, are primarily made up of carbon atoms.

3. **Source of Carbon**: The carbon that contributes to the mass of plants comes from carbon dioxide (CO2) in the atmosphere. Plants absorb carbon dioxide during the process of photosynthesis.

4. **Photosynthesis Process**: During photosynthesis, plants convert carbon dioxide and water into glucose and oxygen using sunlight. This process not only produces energy in the form of glucose but also incorporates carbon from carbon dioxide into the plant's structure.

5. **Conclusion**: Therefore, the correct answer to the question is that most of the mass of organic material in a plant comes from carbon dioxide used during photosynthesis.

**Final Answer**: Most of the mass of organic material of a plant comes from carbon dioxide.

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