Which ingredient was present in higher concentration in GM rice as compared to the usual rice?

Options

A. Protein
B. Carbohydrate (starch)
C. `beta`-carotene
D. `Na^(+)`

Answer

**Step-by-Step Solution:**

1. **Understanding GM Rice**: The question refers to genetically modified (GM) rice, specifically a variety known as "Golden Rice." This rice has been engineered to contain additional nutrients compared to conventional rice.

2. **Identifying the Key Ingredient**: Among the options provided (protein, carbohydrate in the form of starch, beta-carotene, and sodium), we need to identify which ingredient is present in higher concentration in GM rice.

3. **Focus on Beta-Carotene**: Golden Rice was specifically modified to include higher levels of beta-carotene, which is a precursor to vitamin A. This modification aims to combat vitamin A deficiency, which is prevalent in regions where rice is a staple food.

4. **Mechanism of Action**: When consumed, beta-carotene is metabolized in the human body to produce vitamin A, which is essential for various bodily functions, including vision and immune response.

5. **Conclusion**: Based on the information about Golden Rice and its purpose, the ingredient present in higher concentration in GM rice compared to usual rice is **beta-carotene**.

**Final Answer**: C) Beta-carotene

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