Golden rice is

Options

A. antifreeze proteins
B. `beta ` - carotene
C. cry- protein
D. essential micro- nutients

Answer

**Step-by-Step Solution:**

1. **Understanding the Options**: The question presents four options regarding what Golden Rice is. We need to evaluate each option to determine which one accurately describes Golden Rice.

2. **Analyzing Antifreeze Proteins**: The first option is antifreeze proteins. These proteins, known as AFPs, are biological materials that help organisms survive in freezing temperatures. They are primarily found in polar fish. Since Golden Rice is not related to antifreeze proteins, this option is incorrect.

3. **Evaluating Beta-Carotene**: The second option is beta-carotene. Golden Rice is genetically engineered to produce beta-carotene, which is a precursor of vitamin A. This means that Golden Rice is indeed associated with beta-carotene, making this option correct.

4. **Considering Cryoproteins**: The third option refers to cryoproteins, which are toxic crystal proteins encoded by cry genes. These proteins are toxic to insects and are not related to the purpose of Golden Rice. Therefore, this option is also incorrect.

5. **Looking at Essential Micronutrients**: The fourth option mentions essential micronutrients, which are necessary for human health. While Golden Rice does provide some micronutrients, it is specifically known for its beta-carotene content. Thus, this option is not the best description of Golden Rice.

6. **Conclusion**: After analyzing all the options, the most accurate description of Golden Rice is that it is beta-carotene. Therefore, the correct answer is option 2: beta-carotene.

**Final Answer**: Golden Rice is beta-carotene.

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