A cancer causing agent is known as:

Options

A. Oncogene
B. Carcinoma
C. Carcinogen
D. Metastasis

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks for the term that describes a cancer-causing agent.

2. **Analyzing the Options:**
The options provided are:
- A) Oncogene
- B) Carcinoma
- C) Carcinogen
- D) Metastasis

3. **Defining Each Term:**
- **Oncogene:** A gene that has the potential to cause cancer. It is not an agent itself but rather a genetic factor.
- **Carcinoma:** This refers to a type of cancer that begins in the skin or in tissues that line or cover internal organs. It is a classification of cancer, not a causing agent.
- **Carcinogen:** This term specifically refers to any substance, organism, or physical agent that can cause cancer. This is the term we are looking for.
- **Metastasis:** This is the process by which cancer spreads from one part of the body to another. It describes a stage of cancer progression, not a causing agent.

4. **Identifying the Correct Answer:**
Based on the definitions, the correct answer is **C) Carcinogen**, as it directly refers to agents that can cause cancer.

5. **Conclusion:**
Therefore, the answer to the question "A cancer causing agent is known as:" is **Carcinogen**.

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