The autonomously independent self replicating extranuclear DNA imparting cartain factors to some bacterium is called:

Options

A. cosmid
B. plastid
C. plasmid
D. phageinid

Answer

To solve the question, "The autonomously independent self-replicating extranuclear DNA imparting certain factors to some bacterium is called:", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Key Terms**: The question mentions "autonomously independent self-replicating extranuclear DNA." We need to identify what type of DNA fits this description.

2. **Identifying Extranuclear DNA**: Extranuclear DNA refers to DNA that is not located within the nucleus of a cell. In prokaryotes, such as bacteria, DNA is typically found in the cytoplasm.

3. **Self-Replication**: The term "self-replicating" indicates that this DNA can replicate independently of the chromosomal DNA.

4. **Types of Extranuclear DNA**: In bacteria, the most common type of self-replicating extranuclear DNA is plasmids. Plasmids are small, circular, double-stranded DNA molecules that can replicate independently of chromosomal DNA.

5. **Function of Plasmids**: Plasmids often carry genes that provide bacteria with advantageous traits, such as antibiotic resistance or the ability to metabolize certain substances.

6. **Conclusion**: Based on the above points, the correct answer to the question is "plasmid."

### Final Answer:
The autonomously independent self-replicating extranuclear DNA imparting certain factors to some bacterium is called a **plasmid**.

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