Which of the following is not special about `C_(4)` plants ?

Options

A. Responsiveness to high light intensities
B. Presence of Photorespiration
C. Greater productivity
D. Narrow stomatal pores

Answer

To determine which of the following is not special about C4 plants, we need to analyze each option provided:

1. **Responsiveness to high light intensities**: C4 plants are known for their ability to thrive in high light conditions. They have adaptations that allow them to efficiently use light energy, making this characteristic special about them.

2. **Presence of photorespiration**: C4 plants have evolved mechanisms to minimize photorespiration. They have specialized structures (bundle sheath cells) that prevent oxygen from interfering with the photosynthetic process. Therefore, the presence of photorespiration is not a special characteristic of C4 plants; in fact, they are adapted to avoid it.

3. **Greater productivity**: C4 plants are generally more productive than C3 plants, especially in hot and dry environments. This increased productivity is a significant characteristic of C4 plants.

4. **Narrow stomatal pores**: C4 plants have narrow stomatal pores, which help reduce water loss through transpiration. This adaptation is crucial for survival in high-temperature environments.

Based on the analysis of these options, the answer to the question "Which of the following is not special about C4 plants?" is:

**Presence of photorespiration**.

### Step-by-Step Solution:
1. Identify the characteristics of C4 plants.
2. Analyze each option given in the question.
3. Determine which option does not align with the special adaptations of C4 plants.
4. Conclude that the presence of photorespiration is not special about C4 plants.