The following are the major concerns about GM crops and GM foods, except:

Options

A. The GM crops may change the fundamental vegetable nature of plants as the genes from animals are being introduced into crop plants
B. The GM crops may lead to change in the evolutionaty pattern
C. The antibiotic resistance marker genes used to produce GM crops may move from plants to gut microflora of humans and animals and increase the problem of antibiotic resistance in pathogens
D. The introduction of GM crops has reduced to the crop yield

Answer

To solve the question regarding the major concerns about GM crops and GM foods, we need to analyze the provided options and identify which statement does not represent a concern. Here’s a step-by-step breakdown:

### Step 1: Identify the Options
The question presents several statements regarding GM crops and foods. We need to evaluate each one to determine if it is a concern.

### Step 2: Evaluate Each Statement
1. **Statement 1**: GM crops may change the fundamental vegetable nature of plants as genes from animals are being introduced into crop plants.
- **Analysis**: This is a valid concern as it addresses the potential alteration of plant characteristics due to the introduction of animal genes.

2. **Statement 2**: GM crops may lead to changes in evolutionary patterns.
- **Analysis**: This is also a concern because introducing new genes can affect the evolutionary trajectory of plant species.

3. **Statement 3**: The antibiotic-resistant marker gene used to produce GM crops may move from plants to the gut microflora of humans and animals and increase the problem of antibiotic resistance in pathogens.
- **Analysis**: This is a significant concern since it discusses the potential health implications of antibiotic resistance due to GM foods.

4. **Statement 4**: The introduction of GM crops has reduced crop yield.
- **Analysis**: This statement is not a concern because, in reality, GM crops are known to increase crop yield and improve nutritional quality.

### Step 3: Conclusion
After evaluating all the statements, it is clear that the fourth statement is the one that does not represent a concern regarding GM crops and GM foods. Therefore, the answer to the question is:

**Answer**: The introduction of GM crops has reduced the crop yield.

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