Magic bullets are the

Options

A. Recombinant vaccines
B. Monoclonal antibodies
C. Chemotherapy drugs for cancer
D. Anabolic steroids

Explanation

**Step-by-Step Solution:**

1. **Understanding the Term "Magic Bullets":**
- The term "magic bullets" refers to specific therapeutic agents that can target diseases effectively without causing significant side effects. This concept is particularly associated with treatments that can precisely attack pathogens or diseased cells.

2. **Analyzing the Options:**
- **Option A: Recombinant Vaccine**
- Recombinant vaccines are produced using recombinant DNA technology. They stimulate an immune response but are not classified as "magic bullets" since they do not directly target and eliminate diseases in the same manner as antibodies.
- **Option B: Monoclonal Antibodies**
- Monoclonal antibodies are engineered to bind to specific antigens on pathogens or diseased cells. They are designed to target and neutralize these cells, making them a prime example of "magic bullets" in medicine.
- **Option C: Chemotherapy Drugs for Cancer**
- Chemotherapy drugs are used to treat cancer by targeting rapidly dividing cells. While they can be effective, they often affect healthy cells as well, leading to significant side effects. Thus, they do not fit the definition of "magic bullets."
- **Option D: Anabolic Steroids**
- Anabolic steroids are synthetic derivatives of testosterone. They are used to promote muscle growth and are not related to the concept of "magic bullets" in disease treatment.

3. **Identifying the Correct Answer:**
- After analyzing all the options, it is clear that **Option B: Monoclonal Antibodies** is the correct answer, as they are specifically designed to act as "magic bullets" against diseases.

**Final Answer:**
- Magic bullets are the **monoclonal antibodies**.

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