Which of the following is correct ?

Options

A. The proteins encoded by the genes crylAc and cryllAb control cotton bollworms
B. Protein encoded by crylAb controls corn borer
C. Both
D. Proteins encoded by crylAc and crylAb control files

Answer

To solve the question "Which of the following is correct?" regarding the proteins encoded by specific cry genes and their effects on pests, we will analyze the options provided based on our understanding of cry genes and their applications in biotechnology.

### Step-by-Step Solution:

1. **Understanding Cry Genes**:
- Cry genes are derived from the bacterium *Bacillus thuringiensis* (Bt). These genes encode for proteins that act as insecticides against specific pests.
- The proteins produced by these genes are initially in an inactive form known as protoxins.

**Hint**: Remember that cry genes are associated with *Bacillus thuringiensis* and are used in pest control.

2. **Identifying the Options**:
- **Option A**: "The proteins encoded by the genes cry1ac and cry2ab control the cotton bull worms."
- **Option B**: "The protein encoded by cry1ab controls corn borer."
- **Option C**: "The protein encoded by cry1ac and cry1ab controls flies."

**Hint**: Break down each option to see which pests are controlled by the respective cry proteins.

3. **Analyzing Option A**:
- Cry1ac and Cry2ab proteins are known to be effective against cotton bollworms. Thus, this option is correct.

**Hint**: Check the specific pests targeted by each cry protein.

4. **Analyzing Option B**:
- Cry1ab is known to control the corn borer, making this option correct as well.

**Hint**: Verify which cry proteins are effective against corn borer.

5. **Analyzing Option C**:
- Cry1ac and Cry1ab are not specifically known for controlling flies. Therefore, this option is incorrect.

**Hint**: Consider the specific pests that each cry protein is known to target.

6. **Conclusion**:
- Since both Option A and Option B are correct, the overall answer is that both statements are true. Therefore, the correct answer is "both."

**Hint**: When multiple options are correct, look for a combined answer that encompasses all correct statements.

### Final Answer:
The correct answer is that both Option A and Option B are correct, which leads us to conclude that the answer is "both."