Tobacco consumption is known to stimulate secretion of adrenaline and nor-adrenaline. The component causing this could be

Options

A. nicotine
B. tannic acid
C. curaimin
D. catechin.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question:** The question states that tobacco consumption stimulates the secretion of adrenaline and noradrenaline. We need to identify which component of tobacco is responsible for this stimulation.

2. **Identifying Components of Tobacco:** Tobacco contains several chemical substances, among which the most notable is nicotine. Other components mentioned in the options include tannic acid, curamine, and catechin.

3. **Role of Nicotine:** Nicotine is an alkaloid found in tobacco. It has a specific effect on the body, particularly on the adrenal glands.

4. **Mechanism of Action:** When nicotine is consumed, it stimulates the adrenal glands to release adrenaline and noradrenaline into the bloodstream. This release leads to physiological changes such as increased heart rate and elevated blood pressure.

5. **Conclusion:** Based on the information gathered, the component in tobacco that causes the stimulation of adrenaline and noradrenaline secretion is nicotine.

6. **Final Answer:** Therefore, the correct option is **A) nicotine**.

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