The major contribution of Sir J. C Bose in plant physiology is

Options

A. Defined Root pressure
B. Discovered vernalization
C. Explained the Mechanism of translocation of food in plants.
D. Worked on Bioelectrical responses of plants to various stimuli

Answer

**Step-by-Step Solution:**

1. **Understanding the Contributions of Sir J. C. Bose**: Sir Jagadish Chandra Bose was a pioneering scientist in the field of plant physiology and biophysics. He made significant contributions to our understanding of how plants respond to various stimuli.

2. **Analyzing the Options**:
- **Option 1: Defined root pressure** - While root pressure is an important concept in plant physiology, it was not primarily defined by Bose.
- **Option 2: Discover burnalization** - Vernalization is the process of inducing flowering in plants by exposing them to prolonged cold. This was not a major contribution of Bose.
- **Option 3: Explained the mechanism of translocation of food in plants** - Although he contributed to plant physiology, this specific discovery is attributed to other scientists.
- **Option 4: Worked on bioelectrical responses of plants to various stimuli** - This is the most significant contribution of Sir J. C. Bose. He demonstrated that plants have bioelectrical responses to stimuli, which was a groundbreaking discovery at the time.

3. **Identifying the Correct Answer**: Based on the analysis, the correct answer is **Option 4: Worked on bioelectrical responses of plants to various stimuli**.

4. **Conclusion**: Sir J. C. Bose's work on the electrical nature of plant responses marked a significant shift in understanding plant physiology, moving away from the notion that all plant responses were purely chemical.