The introduction of cry gene in Bt cotton was aimed at:

Options

A. providing pest resistance to boll worm
B. dellaying flowering of cotton
C. preventing attack of coleopteran pests
D. preventing use of chemical pesticides

Answer

**Step-by-Step Solution:**

1. **Understanding Bt Cotton**:
- Bt cotton is a genetically modified organism (GMO) that has been engineered to express a specific gene from the bacterium *Bacillus thuringiensis* (Bt). This gene is known as the cry gene.

**Hint**: Remember that Bt cotton is a transgenic plant that incorporates a gene from a bacterium.

2. **Function of the Cry Gene**:
- The cry gene produces a protein called Cry protein, which is toxic to certain insect pests, particularly the cotton bollworm. This protein acts as a natural insecticide.

**Hint**: Focus on the role of the cry gene in pest resistance.

3. **Purpose of Introducing the Cry Gene**:
- The primary aim of introducing the cry gene into cotton plants is to provide them with inherent resistance to pests, thereby reducing the need for chemical pesticides.

**Hint**: Consider the benefits of pest resistance and reduced pesticide use.

4. **Evaluating the Options**:
- Option 1: Providing pest resistance to bollworm - This is a correct statement but not the most comprehensive aim.
- Option 2: Delaying flowering of cotton - This is incorrect.
- Option 3: Preventing attack of Coleopteran pests - This is incorrect as the primary target is the bollworm.
- Option 4: Preventing the use of chemical pesticides - This is also a valid aim as it reduces reliance on chemical pest control.

**Hint**: Analyze each option carefully to determine which one aligns best with the overall goal of Bt cotton.

5. **Choosing the Most Correct Option**:
- While both options 1 and 4 are relevant, the most comprehensive aim of introducing the cry gene is to reduce the reliance on chemical pesticides, making option 4 the best choice.

**Hint**: Prioritize the option that reflects a broader environmental benefit.

**Final Answer**: The introduction of the cry gene in Bt cotton was aimed at preventing the use of chemical pesticides.

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