Which of the following is NOT a part of a cigarette?

Caffeine is not a component of a cigarette, whereas tar, nicotine, and carbon monoxide are all harmful substances found in cigarette smoke.

Tar is a sticky substance that accumulates in the lungs and contributes to respiratory problems and cancer. Nicotine is the addictive chemical that leads to dependence on tobacco. Carbon monoxide is a toxic gas that reduces the oxygen-carrying capacity of blood, leading to various health issues, including heart disease. Caffeine, on the other hand, is primarily associated with coffee and tea and does not have a role in the composition of cigarettes.