Bt cotton is resistant against:

Options

A. Salt
B. Herbicides
C. Insect
D. Drought

Explanation

**Step-by-Step Solution:**

1. **Understanding Bt Cotton**: Bt cotton is a genetically modified organism (GMO) that has been engineered to express a protein from the bacterium Bacillus thuringiensis (Bt). This modification is done to enhance the plant's resistance to certain pests.

2. **Identifying the Source of Resistance**: The term "Bt" refers to the bacterium Bacillus thuringiensis, which produces a specific protein that is toxic to certain insects. This protein is known to create pores in the gut of insects, leading to their death.

3. **Mechanism of Action**: When insects consume parts of the Bt cotton plant, they ingest the toxic protein. This protein disrupts their digestive system, causing swelling and ultimately leading to the insect's death.

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