`C_4`-plants are well adapted to

Options

A. Dry tropical region
B. Temperate regions
C. Arctic regions
D. Low temperature

Answer

### Step-by-Step Solution:

1. **Understanding C4 Plants**: C4 plants are a type of photosynthetic plant that have a unique mechanism for carbon fixation, which allows them to thrive in certain environmental conditions.

2. **Adaptation to Harsh Environments**: C4 plants are well adapted to survive in harsh environments, particularly those that experience high temperatures and low water availability. This adaptation is crucial for their survival in specific ecosystems.

3. **Cran's Anatomy**: C4 plants exhibit a specialized leaf anatomy known as Kranz anatomy. This structure helps in the efficient capture of carbon dioxide and minimizes water loss, making them more efficient in hot and dry conditions compared to C3 plants.

4. **Location of the Calvin Cycle**: In C4 plants, the Calvin cycle occurs in bundle sheath cells, which is different from C3 plants where it occurs in mesophyll cells. This adaptation allows C4 plants to effectively utilize carbon dioxide even when it is scarce.

5. **Preferred Regions**: Due to their adaptations, C4 plants are predominantly found in dry tropical regions, such as deserts. These areas are characterized by extreme temperatures and limited water supply, which aligns with the physiological traits of C4 plants.

6. **Conclusion**: Therefore, C4 plants are well adapted to dry tropical regions, where they can efficiently perform photosynthesis despite the challenging environmental conditions.