Number of stomata and epidermal cells in `1nm^(2)` area of abaxial surface of leaves a, b, c, and d are
`{:("Plant","Number of stomata","Nunber of Epidermal cells"),(a,40,730),(b,60,510),(c,70,450),(d,30,620):}` Identfiy two plants having least stomatal index

Options

A. b and c
B. a and d
C. a and c
D. a and b

Answer

To solve the problem of identifying the two plants with the least stomatal index from the given data, we will follow these steps:

### Step-by-Step Solution:

1. **Understand the Stomatal Index Formula**:
The stomatal index (SI) is calculated using the formula:
\[ SI = \left( \frac{S}{S + E} \right) \times 100 \]
where \( S \) is the number of stomata and \( E \) is the number of epidermal cells.

2. **Gather Data**:
We have the following data for each plant:
- Plant A: 40 stomata, 730 epidermal cells
- Plant B: 60 stomata, 510 epidermal cells
- Plant C: 70 stomata, 450 epidermal cells
- Plant D: 30 stomata, 620 epidermal cells

3. **Calculate Stomatal Index for Each Plant**:
- **For Plant A**:
\[ SI_A = \left( \frac{40}{40 + 730} \right) \times 100 = \left( \frac{40}{770} \right) \times 100 \approx 5.19\% \]
- **For Plant B**:
\[ SI_B = \left( \frac{60}{60 + 510} \right) \times 100 = \left( \frac{60}{570} \right) \times 100 \approx 10.53\% \]
- **For Plant C**:
\[ SI_C = \left( \frac{70}{70 + 450} \right) \times 100 = \left( \frac{70}{520} \right) \times 100 \approx 13.46\% \]
- **For Plant D**:
\[ SI_D = \left( \frac{30}{30 + 620} \right) \times 100 = \left( \frac{30}{650} \right) \times 100 \approx 4.62\% \]

4. **Compare Stomatal Indices**:
Now we compare the calculated stomatal indices:
- Plant A: 5.19%
- Plant B: 10.53%
- Plant C: 13.46%
- Plant D: 4.62%

5. **Identify the Two Plants with the Least Stomatal Index**:
The two plants with the least stomatal indices are:
- Plant D: 4.62%
- Plant A: 5.19%

### Final Answer:
The two plants having the least stomatal index are **Plant D** and **Plant A**.

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