Which substances are commonly associated with physical withdrawal?

The correct answer is related to substances that typically lead to physical withdrawal symptoms upon cessation of use. Narcotics and synthetic narcotics, such as opioids, can create a strong physical dependence in users. When someone who is dependent on these substances stops taking them, they can experience a range of withdrawal symptoms that are often painful and distressing. These can include muscle aches, nausea, vomiting, diarrhea, anxiety, and even more severe symptoms depending on the duration and intensity of use.

Withdrawal from narcotics occurs because the body has adapted to the presence of the drug; it shifts its natural balance and functions based on the ongoing use of the opioid. Therefore, when the drug is no longer present, the body reacts negatively, resulting in these physical withdrawal symptoms.

While the other substances mentioned in the question might also have withdrawal effects in certain contexts, they do not typically present the kind of severe physical withdrawal symptoms seen with narcotics. For example, stimulants and hallucinogens primarily cause psychological withdrawal rather than significant physical symptoms. Alcohol does cause withdrawal symptoms, but caffeine typically leads to milder effects such as headache and fatigue, which are far less severe.