Which one is a laboratory weed ?

Options

A. Penicillium
B. Aspergillus
C. Neurospora
D. Yeast

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a laboratory weed among the given options: Penicillium, Aspergillus, Neurospora, and Yeast.

2. **Analyzing the Options**:
- **Penicillium**: This fungus is known for its role in the production of penicillin, an antibiotic. It is not typically referred to as a laboratory weed.
- **Aspergillus**: This is a genus of fungi that includes species like Aspergillus niger, which is commonly found in damp places and is used in laboratory fermentation processes.
- **Neurospora**: This is a genus of fungi that is used in genetic studies but is not classified as a weed.
- **Yeast**: Specifically, Saccharomyces cerevisiae is used in the production of ethyl alcohol and is not considered a weed.

3. **Identifying the Correct Answer**: Among the options, Aspergillus is the one that is commonly referred to as a laboratory weed due to its prevalence in laboratory settings and its use in fermentation processes.

4. **Conclusion**: Therefore, the correct answer to the question "Which one is a laboratory weed?" is **Aspergillus**.

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