Bt corn been made resistant from corn borer disease by intoduction of the gene

Options

A. crylAb
B. cryllAb
C. `amp^(R)`
D. Trp

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks how Bt corn has been made resistant to corn borer disease through the introduction of a specific gene.

2. **Identifying the Relevant Genes:**
There are two main cry genes associated with pest resistance in crops:
- Cry 1 AB
- Cry 2 AB

3. **Gene Introduction in Bt Corn:**
The gene Cry 1 AB is specifically introduced into the corn plant (Bt corn) to confer resistance against the corn borer pest.

4. **Role of Bacillus thuringiensis:**
The Cry proteins are derived from the bacterium Bacillus thuringiensis (Bt), which produces a toxin that is harmful to certain insects, including the corn borer.

5. **Conclusion:**
Thus, the introduction of the Cry 1 AB gene into corn plants enables them to produce a toxin that protects against corn borer infestations, making the correct answer Cry 1 AB.

**Final Answer:**
Bt corn has been made resistant to corn borer disease by the introduction of the Cry 1 AB gene.

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