Which of the following statements is not correct regarding the genetic modification of crops ?

Options

A. It makes crops more tolerant to abiotic stresses
B. It results in decreased efficiency of mineral usage by plants
C. It helps to reduce post harvest losses
D. It enhances the nutritional value of food

Explanation

To determine which statement is not correct regarding the genetic modification of crops, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Genetic Modification**: Genetic modification involves altering the genetic makeup of crops to enhance certain traits, such as yield, pest resistance, and tolerance to environmental stressors.

2. **Evaluate Statements**: We need to analyze each statement provided in the options regarding genetic modification to identify the incorrect one.

3. **Check for Yield and Desired Traits**: Confirm that genetic modification often results in crops that produce higher yields and desirable traits, which is generally a correct statement.

4. **Assess Tolerance to Abiotic Stressors**: Genetic modification has indeed made crops more tolerant to abiotic stressors such as extreme temperatures, drought, and salinity. This statement is correct.

5. **Examine Reliance on Chemical Pesticides**: Modified crops often have reduced reliance on chemical pesticides due to pest-resistant traits. This statement is also correct.

6. **Look at Post-Harvest Losses**: Genetic modification has been shown to help reduce post-harvest losses, which is another correct statement.

7. **Evaluate Mineral Usage Efficiency**: This is where we need to be careful. The statement regarding decreased efficiency of mineral usage by plants is not correct. Genetic modification actually increases the efficiency of mineral usage, preventing early exhaustion of soil fertility.

8. **Nutritional Value Enhancement**: Genetic modification has enhanced the nutritional value of certain crops, such as golden rice, which is enriched with vitamin A. This statement is correct.

9. **Conclusion**: Based on the analysis, the statement that claims decreased efficiency of mineral usage by plants is not correct. Therefore, this is the answer to the question.

### Final Answer:
The statement that is not correct regarding the genetic modification of crops is that it has decreased the efficiency of mineral usage by plants.

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