Select correct option among the given statements regarding true and false. (a) Nicotine reduces the concentration of haembound oxygen, br (b) Nicotine raises blood pressure and increases heart rate, br ( c ) Smoking is associated with increased incidence of cancers, br (d) Smoking causes oxygen deficiency only in the lungs.

Options

A. (a)T, (b)T, ( c)T, (d)T
B. (a) T, (b) F, (c ) T, (d) F
C. (a) F, (b) F, (c ) T, (d) T
D. (a) T, (b) T, (c ) T, (d) F

Answer

To solve the question regarding the statements about nicotine and smoking, we will analyze each statement one by one to determine whether they are true or false.

### Step-by-Step Solution:

1. **Statement (a): Nicotine reduces the concentration of hemobound oxygen.**
- **Analysis:** Nicotine, when inhaled through smoking, increases the levels of carbon monoxide in the blood. Carbon monoxide binds to hemoglobin more effectively than oxygen, which reduces the amount of oxygen that can be transported in the blood.
- **Conclusion:** This statement is **True**.

2. **Statement (b): Nicotine raises blood pressure and increases heart rate.**
- **Analysis:** Nicotine is a stimulant that activates the sympathetic nervous system, leading to an increase in heart rate and blood pressure. This effect is well-documented and is one of the reasons smoking is harmful to cardiovascular health.
- **Conclusion:** This statement is **True**.

3. **Statement (c): Smoking is associated with increased incidence of cancers.**
- **Analysis:** Smoking is a major risk factor for various types of cancer, particularly lung cancer. Numerous studies have shown a strong correlation between smoking and increased cancer incidence.
- **Conclusion:** This statement is **True**.

4. **Statement (d): Smoking causes oxygen deficiency only in the lungs.**
- **Analysis:** While smoking does lead to oxygen deficiency in the lungs due to reduced hemoglobin oxygen saturation, the effects of smoking extend beyond the lungs. The increased carbon monoxide levels affect the entire body, leading to systemic oxygen deficiency.
- **Conclusion:** This statement is **False**.

### Final Summary:
- Statement (a): True
- Statement (b): True
- Statement (c): True
- Statement (d): False

The correct answer is that statements (a), (b), and (c) are true, while statement (d) is false.