Which statement about genetically modified (GM) food is false ?

Options

A. Scientists have used genetic modification, in various forms, as a mean of improving crop yields, crop quality, and pest resistance for many years
B. Genetic modification includes products made by artifical mutagenesis and by non-natural crosses between unrelated species
C. A mojor difficulty in labelling foods as 'GM-free' is that it is virtually impossible to measure genetically modified DNA or protein molecules in most food made from GM crops
D. The recent decision by McCain Foods to stop processing GM potatoes means that they will eventually use less pesticides to produce the potatoes that are required to make fries.

Explanation

To determine which statement about genetically modified (GM) food is false, we will analyze each of the provided statements step by step.

### Step-by-Step Solution:

1. **Statement 1: Scientists have used genetic modification in various forms as a means of improving crop yield, crop quality, and pest resistance for many years.**
- This statement is true. Genetic modification has indeed been used to enhance crop yield, quality, and resistance to pests. The primary goal of genetic modification is to improve agricultural productivity.

2. **Statement 2: Genetic modification includes products made by artificial mutagenesis or by non-natural crosses between unrelated species.**
- This statement is also true. Genetic modification can involve artificial mutagenesis (inducing mutations) and hybridization between unrelated species to create new traits in plants.

3. **Statement 3: The major difficulty in labeling foods as GM-free is that it is virtually impossible to measure genetically modified DNA or protein molecules in most food made from GM crops.**
- This statement is true as well. It is challenging to detect the presence of genetically modified DNA or proteins in food products, making it difficult to label them accurately as GM-free.

4. **Statement 4: The recent decision by McCain Food to stop processing GM potatoes means that they will eventually use less pesticide to produce the potatoes that are required to make fries.**
- This statement is false. The production of GM food often involves the incorporation of pest resistance genes, which can reduce the need for pesticide use. However, the statement incorrectly implies that stopping the processing of GM potatoes will lead to less pesticide use, which is misleading. GM crops are specifically designed to be more resistant to pests, and discontinuing their use may not necessarily lead to reduced pesticide application.

### Conclusion:
Based on the analysis, the false statement about genetically modified (GM) food is **Statement 4**.

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