Which of the following statement is not correct ?

Options

A. Some tranquilizers function by inhibiting the enzymes which catalyse the degradation of noradrenaline
B. Tranquiiizers are narcotic drugs
C. Tranquilizers are chemical compounds that do not affect the message transfer fro nerve to receptor.
D. Tranquilizers are chemical compounds that can relieve pain and fever

Explanation

To determine which statement about tranquilizers is not correct, let's analyze each option step by step.

### Step 1: Analyze Option A
**Statement:** Some tranquilizers function by inhibiting the enzymes which catalyze the degradation of noradrenaline.

**Analysis:** This statement is correct. Some tranquilizers do inhibit enzymes that break down noradrenaline, which can help in managing mood and anxiety.

### Step 2: Analyze Option B
**Statement:** Tranquilizers are narcotic drugs.

**Analysis:** This statement is also correct. Tranquilizers can be classified as narcotic drugs because they have sedative effects and are used to treat anxiety and mental disorders.

### Step 3: Analyze Option C
**Statement:** Tranquilizers are the chemical compounds that do not affect the message transfer from nerve to receptors.

**Analysis:** This statement is correct. Tranquilizers work by altering neurotransmitter activity, which can affect how messages are transmitted between nerves and receptors.

### Step 4: Analyze Option D
**Statement:** Tranquilizers are the chemical compounds that can relieve pain and fever.

**Analysis:** This statement is incorrect. Tranquilizers are primarily used to treat anxiety and mental disorders, not to relieve pain and fever. Pain relief is typically associated with analgesics, not tranquilizers.

### Conclusion
After analyzing all the options, we find that **Option D** is the statement that is not correct.

### Final Answer
**The statement that is not correct is:** Tranquilizers are the chemical compounds that can relieve pain and fever.

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