The structure employed by White for first successful tissue culture was

Options

A. Root of Carrot
B. Root of Tomato
C. Leaf cells
D. Apical meristem.

Answer

To solve the question regarding the structure employed by White for the first successful tissue culture, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the specific structure used by White in his first successful tissue culture experiment.

2. **Identify the Scientist**: The scientist in question is White, who is known for his contributions to tissue culture techniques.

3. **Review the Options**: The options provided are:
- a. Root of carrot
- b. Root of tomato
- c. Leaf cells
- d. Apical meristem

4. **Recall Historical Context**: White's work in tissue culture involved using plant parts to grow new tissues in a controlled environment, typically a nutrient medium.

5. **Select the Correct Structure**: Based on historical records, White successfully used the roots of tomato plants in his experiments.

6. **Conclude the Answer**: Therefore, the correct answer to the question is option **B: Root of tomato**.

### Final Answer:
The structure employed by White for the first successful tissue culture was **B: Root of tomato**.

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