The two most important property of Malignant tumors are :

Options

A. metastasis and angiogenesis
B. metastasis and contact inhibition
C. metastasis and apoptosis
D. metastasis and controlled division

Answer

To answer the question regarding the two most important properties of malignant tumors, we can break down the information provided in the video transcript step by step.

### Step-by-Step Solution:

1. **Understanding Malignant Tumors**:
- Malignant tumors are cancerous growths that are characterized by their ability to invade nearby tissues and spread throughout the body. They do not have clear boundaries, making them more dangerous than benign tumors.

**Hint**: Remember that malignant tumors are cancerous and invasive.

2. **Key Property - Metastasis**:
- One of the defining features of malignant tumors is metastasis. This refers to the process by which cancer cells spread from the original tumor site to other parts of the body, forming new tumors. This ability to metastasize makes malignant tumors particularly dangerous.

**Hint**: Metastasis is the process that allows cancer to spread.

3. **Key Property - Angiogenesis**:
- The second important property of malignant tumors is angiogenesis. This is the formation of new blood vessels that supply nutrients and oxygen to the tumor. For malignant tumors to grow beyond a certain size (a few millimeters), they require a blood supply, which is facilitated by angiogenesis.

**Hint**: Angiogenesis is crucial for tumor growth as it provides necessary nutrients.

4. **Eliminating Incorrect Options**:
- The other options provided (contact inhibition, apoptosis, controlled division) do not accurately describe the properties of malignant tumors:
- **Contact Inhibition**: Malignant tumors often do not exhibit contact inhibition, allowing them to continue growing uncontrollably.
- **Apoptosis**: Malignant tumors evade apoptosis, which is programmed cell death that helps eliminate damaged cells.
- **Controlled Division**: Malignant tumors are characterized by uncontrolled cell division, not controlled division.

**Hint**: Focus on the characteristics that differentiate malignant tumors from normal cells.

5. **Conclusion**:
- Based on the analysis, the two most important properties of malignant tumors are **metastasis** and **angiogenesis**.

### Final Answer:
The two most important properties of malignant tumors are **metastasis** and **angiogenesis**.