In a mixture, DNA fragments are separated by:

Options

A. Restriction digestion
B. Electrophoresis
C. Polymerase chain reaction
D. Bioprocess engineering

Answer

To answer the question "In a mixture, DNA fragments are separated by:", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Options**:
- The options provided are Restriction Digestion, Electrophoresis, Polymerase Chain Reaction (PCR), and Bioprocess Engineering.
- We need to identify which of these methods is specifically used for separating DNA fragments.

2. **Analyzing Restriction Digestion**:
- Restriction Digestion is a process that involves cutting DNA into smaller fragments using restriction enzymes.
- While this method does create fragments, it does not separate them from a mixture.

3. **Analyzing Electrophoresis**:
- Electrophoresis is a technique used to separate DNA fragments based on their size and charge.
- In this method, DNA is placed in a gel matrix and an electric current is applied. The negatively charged DNA molecules move towards the positive electrode, allowing for separation based on size.
- This is the primary method used for separating DNA fragments in a mixture.

4. **Analyzing Polymerase Chain Reaction (PCR)**:
- PCR is a technique used for amplifying DNA, meaning it makes many copies of a specific DNA segment.
- It does not separate DNA fragments; rather, it increases the quantity of a particular DNA sequence.

5. **Analyzing Bioprocess Engineering**:
- Bioprocess Engineering involves the design and development of equipment and processes for the production of biological products.
- It is not specifically related to the separation of DNA fragments.

6. **Conclusion**:
- Based on the analysis, the correct method for separating DNA fragments in a mixture is **Electrophoresis**.

### Final Answer:
In a mixture, DNA fragments are separated by **Electrophoresis**.

---