Salk's vaccine has

Options

A. Polio toxoids
B. attenuated polio virus
C. T.B. toxoids
D. inactivated polio virus

Answer

**Step-by-Step Solution:**

1. **Identify the Vaccine in Question:** The question asks about Salk's vaccine, which is specifically known for its role in preventing polio.

2. **Understand the Components of Salk's Vaccine:** Salk's vaccine is made using inactivated polio virus. This means that the virus is killed or inactivated so that it cannot cause disease, but it can still provoke an immune response.

3. **Evaluate the Options Provided:**
- **Option 1: Polio toxoids** - This option is incorrect because toxoids are inactivated toxins, not viruses.
- **Option 2: Attenuated polio viruses** - This option is also incorrect because attenuated viruses are live but weakened forms of the virus, which is not the case for Salk's vaccine.
- **Option 3: TB toxoids** - This option is incorrect as it refers to a vaccine for tuberculosis, not polio.
- **Option 4: Inactivated polio virus** - This is the correct option as it accurately describes the composition of Salk's vaccine.

4. **Conclusion:** Based on the evaluation of the options, the correct answer is that Salk's vaccine has inactivated polio virus.

**Final Answer:** Salk's vaccine has inactivated polio virus.

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