Mark the incorrect statement.

Options

A. Guttation is observed when root pressure is high and transpiration is low
B. Root pressure is a negative hydrostatic pressure
C. Root pressure develops due to active solute accumulation in root xylem
D. Root pressure provides only a modest push in the overall process of water transport

Answer

To solve the question "Mark the incorrect statement," we will analyze each statement provided and determine which one is incorrect.

### Step-by-Step Solution:

1. **Analyze the First Statement:**
- The statement is: "Guttation is observed when the root pressure is high and the transpiration is low."
- **Evaluation:** This statement is correct. Guttation occurs when root pressure is high, and transpiration is low, leading to the exudation of water droplets from the leaves.

2. **Analyze the Second Statement:**
- The statement is: "Root pressure is the negative hydrostatic pressure."
- **Evaluation:** This statement is incorrect. Root pressure is actually a positive hydrostatic pressure that develops in the xylem of roots due to the active accumulation of solutes.

3. **Analyze the Third Statement:**
- The statement is: "Root pressure develops due to the active solute accumulation in the root xylem."
- **Evaluation:** This statement is correct. Root pressure is generated when solutes are actively absorbed into the root xylem, causing water to move into the xylem by osmosis and creating pressure.

4. **Analyze the Fourth Statement:**
- The statement is: "Root pressure provides only a modest push in the overall process of the water transport."
- **Evaluation:** This statement is also correct. Root pressure does contribute to water transport, but it is generally considered to provide only a modest push compared to the pull created by transpiration.

### Conclusion:
- The incorrect statement is the **second statement**: "Root pressure is the negative hydrostatic pressure."