Which one of the following statements is correct ?

Options

A. Heroin accelerates body functions.
B. Malignant tumours may exhibit metastasis
C. Patients who have undergone surgery are given cannabinoid to relieve pain.
D. Benign tumours show the property of metastasis.

Answer

To determine which statement is correct, we will analyze each option one by one.

### Step-by-Step Solution:

1. **Analyze Option A**:
- Statement: "Heroin accelerates body function."
- Explanation: Heroin is known to be a depressant, which means it slows down body functions rather than accelerating them. Therefore, this statement is incorrect.

2. **Analyze Option B**:
- Statement: "Malignant tumors may exhibit metastasis."
- Explanation: Malignant tumors are indeed cancerous and have the ability to spread to other parts of the body through the bloodstream or lymphatic system, leading to the formation of secondary tumors. This process is known as metastasis. Therefore, this statement is correct.

3. **Analyze Option C**:
- Statement: "Patients who have undergone surgery are given cannabinoids to relieve pain."
- Explanation: Cannabinoids are classified as hallucinogens and are not typically used for pain relief in surgical patients. Instead, opioids like morphine are commonly administered for pain management post-surgery. Thus, this statement is incorrect.

4. **Analyze Option D**:
- Statement: "Benign tumors show the property of metastasis."
- Explanation: Benign tumors do not spread to other parts of the body; they remain localized. Therefore, this statement is also incorrect.

### Conclusion:
The only correct statement among the options is **Option B: "Malignant tumors may exhibit metastasis."**