Cancer causing viruses are known as

Options

A. Retro virus
B. Oncogenic virus
C. Flavo virus
D. Adeno virus

Answer

**Step-by-Step Solution:**

1. **Understanding Cancer**: Cancer is defined as uncontrolled cell division, where cells grow and divide in an abnormal manner, failing to die when they should. This leads to the formation of tumors.

2. **Identifying Cancer-Causing Viruses**: Viruses that can lead to cancer are specifically known as oncogenic viruses. These viruses can alter the genetic material of host cells, promoting uncontrolled growth and division.

3. **Evaluating the Options**:
- **Option 1: Retrovirus**: Retroviruses, such as HIV, are RNA viruses that do not primarily cause cancer. They replicate by converting their RNA into DNA and integrating it into the host's genome, but they are not classified as oncogenic.
- **Option 2: Oncogenic Virus**: Oncogenic viruses are directly responsible for causing cancer. Examples include Hepatitis B, Hepatitis C, and Human Papillomavirus (HPV). This option is correct.
- **Option 3: Flavivirus**: Flaviviruses, such as those causing Dengue and Yellow Fever, are RNA viruses but do not cause cancer. They are transmitted through vectors like mosquitoes.
- **Option 4: Adenovirus**: Adenoviruses are DNA viruses that primarily cause respiratory illnesses and are not associated with cancer.

4. **Conclusion**: After evaluating all options, the correct answer is **Option 2: Oncogenic Virus**, as these are the viruses known to cause cancer.

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