In leaves of `C_4` plants sugars are synthesized in
Stroma of chloroplast of mesophyll cells
Grana of chloroplast of mesophyll cells
Sieve tube elements of phloem
Bundle sheath cells

Options

A. Stroma of chloroplast of mesophyll cells
B. Grana of chloroplast of mesophyll cells
C. Sieve tube elements of phloem
D. Bundle sheath cells

Answer

To solve the question regarding where sugars are synthesized in the leaves of C4 plants, we can follow these steps:

### Step-by-Step Solution:

1. **Understand C4 Plants**: C4 plants are a specific group of plants that have a unique photosynthetic pathway and anatomy known as Kranz anatomy. This adaptation allows them to efficiently fix carbon dioxide in environments where CO2 levels are low or temperatures are high.

**Hint**: Remember that C4 plants have a special structure in their leaves that distinguishes them from C3 plants.

2. **Identify the Key Cells**: In C4 plants, there are two main types of cells involved in photosynthesis: mesophyll cells and bundle sheath cells.

**Hint**: Think about the roles of different cell types in photosynthesis and how they might contribute to sugar synthesis.

3. **Location of Sugar Synthesis**: The Calvin cycle, which is crucial for sugar production, occurs in the bundle sheath cells of C4 plants. This is where the enzyme ribulose bisphosphate carboxylase/oxygenase (RuBisCO) is located, which is essential for the fixation of carbon dioxide into sugars.

**Hint**: Focus on where the enzyme RuBisCO is found, as this will guide you to the correct location of sugar synthesis.

4. **Eliminate Incorrect Options**:
- **Stroma of chloroplast of mesophyll cells**: While the stroma is involved in the Calvin cycle, in C4 plants, the Calvin cycle occurs in the bundle sheath cells, not mesophyll cells.
- **Grana of chloroplast of mesophyll cells**: Grana are involved in the light-dependent reactions, not directly in sugar synthesis.
- **Sieve tube elements of phloem**: These are involved in the transport of sugars, not their synthesis.

**Hint**: Consider the functions of each option and whether they are involved in the synthesis or transport of sugars.

5. **Final Answer**: Based on the above reasoning, the correct answer is that sugars in C4 plants are synthesized in the **bundle sheath cells**.

### Conclusion:
The answer to the question is: **Bundle sheath cells**.