Which statement about tobacco use and its health effects is true according to basic medical and public health knowledge?

Introduction / Context:
Tobacco use is a major cause of preventable disease and death worldwide. Different forms of tobacco, including smoked and smokeless products, have serious health consequences. Exam questions often test whether students can separate accurate health information from myths or misleading claims. This question presents several statements about tobacco and asks which one is medically accurate, focusing on emphysema, stroke risk, addiction, and the idea that smoking “relaxes” people.

Given Data / Assumptions:
- One option states that smoking can cause emphysema and increase stroke risk.
- Another claims that smokeless tobacco can cause cancer but is not addictive.
- A third suggests that smoking relaxes people by lowering heart rate.
- One option asserts that all of the above statements are true.
- We assume standard medical and public health knowledge on the effects of tobacco use.

Concept / Approach:
Smoking tobacco exposes the lungs and blood vessels to harmful chemicals. Long term smoking damages the air sacs (alveoli) in the lungs and can cause chronic obstructive pulmonary disease (COPD), including emphysema. Smoking also damages blood vessels, increases blood clot risk, and raises blood pressure, all of which increase the risk of strokes. So the first statement is accurate. Smokeless tobacco (such as chewing tobacco or snuff) can indeed cause cancers of the mouth, throat, and pancreas, but it is also addictive because it contains nicotine, a highly addictive drug. Therefore, the claim that smokeless tobacco is not addictive is false. The idea that smoking relaxes people by lowering heart rate is misleading; nicotine actually tends to increase heart rate and blood pressure. People may feel temporary relief from withdrawal, but this is not a true healthy relaxation. Therefore, only the first statement about emphysema and strokes is correct.

Step-by-Step Solution:
Step 1: Evaluate the first statement: smoking can cause emphysema and increase stroke risk. This matches medical evidence about lung damage and cardiovascular disease from smoking. Step 2: Evaluate the second statement: smokeless tobacco can cause cancer but is not addictive. This is partly correct about cancer but wrong about addiction, because nicotine in smokeless tobacco is highly addictive. Step 3: Evaluate the third statement: smoking relaxes because it lowers heart rate. This contradicts the known effects of nicotine, which usually increase heart rate and blood pressure. Step 4: Recognise that if some statements are false, the option saying all of the above are true cannot be correct. Step 5: Conclude that only the statement in option A is fully true.

Verification / Alternative check:
Health guidelines from medical organisations clearly list emphysema, chronic bronchitis, heart attacks, and strokes as major risks of smoking. They also warn that smokeless tobacco is addictive and can lead to oral cancers. Information leaflets and public health campaigns stress that nicotine is highly addictive regardless of how tobacco is used. They also explain that the feeling of relaxation after smoking is related to relief from withdrawal symptoms, not to a true healthy calming of the cardiovascular system. These sources confirm that option A is correct and the other statements are misleading or false.

Why Other Options Are Wrong:
- Smokeless tobacco can lead to cancer but is not addictive is wrong because smokeless tobacco is strongly addictive due to nicotine content.
- Smoking relaxes people because it lowers the heart rate is wrong; nicotine usually raises heart rate and blood pressure and harms blood vessels.
- All of the statements given above about tobacco use are true is incorrect because at least two of the earlier statements contain false claims.

Common Pitfalls:
Some learners may be misled by myths or advertisements that portray smokeless tobacco as safer or non addictive. Others may believe that the calming feeling after smoking means it is medically relaxing, without understanding the role of addiction and withdrawal. It is important to rely on scientific evidence rather than popular beliefs. Remember that all forms of tobacco carry serious health risks, and nicotine is addictive in smoked and smokeless products alike. Keeping these facts in mind helps identify the single accurate statement in exams.

Final Answer:
The true statement is that Smoking can lead to chronic lung diseases such as emphysema and can also increase the risk of strokes.