What are biological response modifiers used for the treatment of cancer?

Explanation

**Step-by-Step Solution:**

1. **Definition of Biological Response Modifiers**: Biological response modifiers (BRMs) are substances that modify the immune response of a cancer patient. They can enhance the body's natural defenses against cancer.

*Hint: Think about how the immune system interacts with cancer cells and how modifiers can influence this interaction.*

2. **Function of Biological Response Modifiers**: The primary function of BRMs is to activate the immune system. By doing so, they help the body recognize and destroy tumor cells more effectively.

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