Hepatitis B vaccine is a:

Options

A. combined vaccine
B. DNA vaccine
C. recombinant antigen vaccine
D. polysaccharide vaccine

Answer

**Step-by-Step Solution:**

1. **Understanding the Types of Vaccines**: The question asks about the classification of the Hepatitis B vaccine. There are different types of vaccines, including combined vaccines, DNA vaccines, recombinant antigen vaccines, and polysaccharide vaccines.

2. **Identifying the Production Method**: The Hepatitis B vaccine is produced using recombinant DNA technology. This process involves inserting the DNA of the Hepatitis B virus into another organism, which in this case is a yeast cell.

3. **Role of the Yeast Cell**: Once the DNA of the Hepatitis B virus is inserted into the yeast cell, the yeast cell begins to produce the surface antigens of the virus. These antigens are crucial as they stimulate the immune response in the body.

4. **Defining Recombinant Antigen Vaccines**: Vaccines that are made using recombinant DNA technology and contain antigens produced by the host organism (like yeast) are classified as recombinant antigen vaccines.

5. **Conclusion**: Based on the production method and the type of antigens used, the Hepatitis B vaccine is classified as a recombinant antigen vaccine.

**Final Answer**: The Hepatitis B vaccine is a recombinant antigen vaccine.

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