Which of the following genes were introduced in cotton to protect it from cotton bollworms ?

Options

A. CryAc and CryAb
B. BtAc and BtAb
C. CrylAc and CryllAb
D. Nif genes

Explanation

To solve the question regarding which genes were introduced in cotton to protect it from cotton bollworms, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Problem**: The question asks which genes were introduced into cotton to protect it from cotton bollworms, a type of insect that damages cotton crops.

2. **Understand the Source of Protection**: The protection against cotton bollworms is provided by a toxin produced by the bacterium *Bacillus thuringiensis* (Bt). This bacterium produces a protein that is toxic to certain insects.

3. **Identify the Toxin**: The specific toxin produced by *Bacillus thuringiensis* is known as the Bt toxin. This toxin is effective against various insect pests, including cotton bollworms.

4. **Identify the Genes**: The genes responsible for producing the Bt toxin in genetically modified cotton are known as cry genes. The two specific cry genes that have been introduced into cotton are:
- **Cry1AC**
- **Cry2AB**

5. **Conclusion**: The genetically modified cotton that contains these genes is referred to as Bt cotton. Therefore, the correct answer to the question is that the genes introduced in cotton to protect it from cotton bollworms are **Cry1AC and Cry2AB**.

### Final Answer:
The genes introduced in cotton to protect it from cotton bollworms are **Cry1AC and Cry2AB**.

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