Select the correct events leading to the opening of the stomata
(i) Decline in guard cell solutes
(ii) Lowering of osmotic potential of guard cells
(iii) Rise in potassium levels in guard cells
(iv) Movement of water from neighbouring cells into guard cells
(v) Guard cells becoming flaccid

Options

A. (i) and (v) only
B. (ii), (iii) and (iv) only
C. (i), (iii) and (iv) only
D. (ii), (iv) and (v) only

Answer

To determine the correct events leading to the opening of the stomata, we will analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Analyze the first statement: Decline in guard cell solutes.**
- This statement is incorrect. For stomata to open, guard cells need to accumulate solutes, not decline. A decline in solutes would lead to a loss of turgor pressure, causing the stomata to close.

2. **Analyze the second statement: Lowering of osmotic potential of guard cells.**
- This statement is correct. Lowering the osmotic potential in guard cells allows for the uptake of water, which is essential for the opening of the stomata. When solutes are actively transported into guard cells, the osmotic potential decreases, leading to water influx.

3. **Analyze the third statement: Rise in potassium levels in guard cells.**
- This statement is correct. The rise in potassium ions (K+) within the guard cells is crucial for stomatal opening. The accumulation of potassium ions causes water to enter the guard cells, increasing their turgor pressure.

4. **Analyze the fourth statement: Movement of water from neighboring cells into guard cells.**
- This statement is correct. The movement of water from adjacent cells into the guard cells occurs due to the osmotic gradient created by the influx of potassium ions. This water movement leads to the guard cells becoming turgid, which is necessary for the stomata to open.

5. **Analyze the fifth statement: Guard cells becoming flaccid.**
- This statement is incorrect. For stomata to open, guard cells must become turgid, not flaccid. Flaccid guard cells would indicate a loss of water and pressure, resulting in the closure of the stomata.

### Conclusion:
The correct events leading to the opening of the stomata are:
- Lowering of osmotic potential of guard cells (ii)
- Rise in potassium levels in guard cells (iii)
- Movement of water from neighboring cells into guard cells (iv)

Thus, the correct answer is the combination of statements (ii), (iii), and (iv).