During isolation of genetic material, the chemical used to precipitate out the purified DNA is

Options

A. a) bromophenol blue
B. b) chilled ethanol
C. c) ethidium bromide
D. d) both (a) and (c)

Explanation

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks for the chemical used to precipitate purified DNA during the isolation of genetic material.

2. **Analyze the Options**:
- **Option A: Bromophenol blue**: This is a dye used for staining and does not play a role in DNA precipitation.
- **Option B: Chilled ethanol**: This is commonly used in laboratory procedures to precipitate DNA from a solution.
- **Option C: Ethidium bromide**: This chemical is used for visualizing DNA after it has been separated by gel electrophoresis, not for precipitation.
- **Option D: Both A and C**: Since both A and C are incorrect, this option is also incorrect.

3. **Identify the Correct Answer**: After analyzing the options, it is clear that the chemical used to precipitate out the purified DNA is **chilled ethanol**.

4. **Conclusion**: The correct answer is **Option B: Chilled ethanol**.

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