Bacteriophages were discovered by

Options

A. Twort
B. De Herelle
C. Takahashi and Rawlins
D. Stanley.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who discovered bacteriophages. Bacteriophages, or phages, are viruses that infect bacteria.

2. **Evaluating the Options**: The options provided are:
- A) Twart
- B) D. Hurley
- C) Taka Hashi and Rawlings
- D) Stanley

3. **Identifying the Correct Answer**:
- **Option A (Twart)**: This is the correct answer. Frederick Twart is credited with the discovery of bacteriophages in 1915.
- **Option B (D. Hurley)**: This option is incorrect. D. Hurley is known for being a co-discoverer but not the original discoverer.
- **Option C (Taka Hashi and Rawlings)**: This option is also incorrect as they are known for their work in stem cell research, not bacteriophages.
- **Option D (Stanley)**: This option is incorrect as well. Stanley is known for his work related to the isolation of the tobacco mosaic virus, not bacteriophages.

4. **Conclusion**: Based on the evaluation, the correct answer is **Option A (Twart)**, as he was the original discoverer of bacteriophages.

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