Transformation of the normal cells into the cancerous neoplastic cells may be induced by : - (i) x-rays (ii) Chemical agents (iii) `gamma`-rays (iv) Oncovirus (v) Smoking (vi) U.V. rays

Options

A. i, iii, vi
B. i, iii, iv, vi
C. i, ii, iii, iv, v, vi
D. i, ii, iii, iv, vi

Answer

To answer the question regarding the transformation of normal cells into cancerous neoplastic cells, we need to identify the various agents that can induce this transformation. Let's analyze each of the provided options step by step:

### Step 1: Understanding Carcinogens
Carcinogens are agents that can cause cancer by inducing changes in cellular DNA, leading to uncontrolled cell growth.

### Step 2: Evaluating Each Option
1. **X-rays**:
- X-rays are a form of ionizing radiation. They can penetrate tissues and cause DNA damage, which can lead to cancer.
- **Conclusion**: Yes, X-rays can induce transformation into cancerous cells.

2. **Chemical Agents**:
- Various chemicals, such as benzopyrene, asbestos, and heavy metals, are known carcinogens. Prolonged exposure to these chemicals can lead to mutations and cancer.
- **Conclusion**: Yes, chemical agents can induce transformation into cancerous cells.

3. **Gamma-rays**:
- Gamma-rays are also a type of ionizing radiation similar to X-rays. They can cause DNA damage and are associated with an increased risk of cancer.
- **Conclusion**: Yes, gamma-rays can induce transformation into cancerous cells.

4. **Oncovirus**:
- Oncoviruses, such as the Epstein-Barr virus and human T-lymphotropic virus (HTLV), can integrate into the host's DNA and cause cancer.
- **Conclusion**: Yes, oncoviruses can induce transformation into cancerous cells.

5. **Smoking**:
- Smoking is a major risk factor for several types of cancer, including lung and throat cancer. It introduces numerous carcinogenic substances into the body.
- **Conclusion**: Yes, smoking can induce transformation into cancerous cells.

6. **U.V. rays**:
- Ultraviolet (UV) rays from the sun can cause skin damage and are a well-known risk factor for skin cancers, such as melanoma.
- **Conclusion**: Yes, UV rays can induce transformation into cancerous cells.

### Final Conclusion:
All the options provided (i.e., X-rays, chemical agents, gamma-rays, oncovirus, smoking, and UV rays) can induce the transformation of normal cells into cancerous neoplastic cells. Therefore, the answer to the question is that all the listed agents can lead to cancer.