Mango trees do not and cannot grow in temperate regions. The most important environmental factor responsible for its is

Options

A. soil
B. temperature
C. water
D. light

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question states that mango trees do not and cannot grow in temperate regions. We need to identify the most important environmental factor responsible for this inability.

2. **Analyzing the Options**: The options provided are soil, temperature, water, and light. We need to evaluate which of these factors is most critical for the growth of mango trees in temperate regions.

3. **Evaluating Temperature**: Temperature is a crucial factor for plant growth. Mango trees thrive in warm climates and require specific temperature ranges for optimal growth. In temperate regions, the climate is generally cooler, which can hinder the growth of mango trees.

4. **Role of Enzymes**: Enzymes are biological catalysts that facilitate various biochemical reactions necessary for plant growth. Temperature directly influences enzyme activity. If the temperature is too low, enzyme activity decreases, which can affect the plant's metabolism and physiological functions.

5. **Impact on Basal Metabolism**: The basal metabolism of a plant is essential for its growth and development. If the temperature is not suitable, the metabolic processes will be adversely affected, leading to poor growth or inability to grow at all.

6. **Conclusion**: Given that mango trees require warm temperatures for their enzymes to function effectively and for their metabolic processes to occur, the most important environmental factor responsible for their inability to grow in temperate regions is indeed temperature.

7. **Final Answer**: The correct answer is **temperature**.

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