Terramycin is obtained from:

Options

A. a) Streptomyces remosus
B. b) S. venezuelae
C. c) S. aureofaciens
D. d) S. fradiae

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the source of Terramycin, which is an antibiotic.

2. **Identifying the Options**: The options given are:
- Streptomyces rumosus
- Streptomyces venezuela
- Ornithischians
- Streptomyces tridium

3. **Recognizing the Type of Antibiotic**: Terramycin is known to be a broad-spectrum antibiotic that falls under the tetracycline group.

4. **Researching the Origin of Terramycin**: Initially, Terramycin was isolated from soil samples containing actinomycetes, which are a type of bacteria.

5. **Identifying the Correct Species**: The specific species from which Terramycin was first isolated is Streptomyces ramosus. This species is part of the genus Streptomyces, which includes various other species mentioned in the options.

6. **Evaluating the Options**:
- Streptomyces rumosus: Incorrect
- Streptomyces venezuela: Incorrect
- Ornithischians: Incorrect (not related to bacteria)
- Streptomyces tridium: Incorrect
- **Correct Answer**: Streptomyces ramosus

7. **Conclusion**: The correct answer to the question is that Terramycin is obtained from **Streptomyces ramosus**.

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