Tropical plants have a ___ temperature optimum than the plants adapted to temperate climates.

Options

A. lower
B. equal
C. higher
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks us to compare the temperature optimum of tropical plants with that of plants adapted to temperate climates.

2. **Identifying Tropical Plants:** Tropical plants are those that thrive in tropical regions, which are characterized by high temperatures and humidity. These plants are adapted to these warm conditions.

3. **Identifying Temperate Plants:** In contrast, temperate plants are found in temperate climates, which have moderate to low temperatures. These plants are adapted to cooler conditions compared to tropical plants.

4. **Temperature Optimum:** The term "temperature optimum" refers to the ideal temperature range at which a plant can perform photosynthesis most efficiently.

5. **C4 and C3 Plants:**
- Tropical plants, which are often C4 plants, are adapted to higher temperatures and show an increased rate of photosynthesis at these temperatures.
- Temperate plants, which are typically C3 plants, perform best at lower temperatures.

6. **Conclusion:** Since tropical plants are adapted to higher temperatures, we conclude that tropical plants have a **higher** temperature optimum than plants adapted to temperate climates.

**Final Answer:** Tropical plants have a **higher** temperature optimum than the plants adapted to temperate climates.

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