**Core Concept**
The question requires the identification of withdrawal symptoms from various substances. The correct answer involves understanding the characteristic withdrawal symptoms associated with each substance.

**Why the Correct Answer is Right**
The correct answer is based on the distinct withdrawal symptoms exhibited by each substance. For case 1, the symptoms of high blood pressure, tachycardia, tremors, auditory and visual hallucinations, hepatomegaly, and disorientation are characteristic of withdrawal from alcohol. Alcohol withdrawal can lead to a condition known as delirium tremens (DTs), which is a life-threatening condition.

The symptoms in case 2, including yawning, diarrhea, diaphoresis, mydriasis, high fever, rhinorrhea, and piloerection, are characteristic of withdrawal from amphetamines. Amphetamine withdrawal can lead to a condition known as amphetamine psychosis, which is characterized by hallucinations and delusions.

**Why Each Wrong Option is Incorrect**
**Option A:** Cannabis withdrawal symptoms typically include irritability, mood and sleep difficulties, decreased appetite, cravings, restlessness, and a low-grade fever. These symptoms do not match those described in the cases.

**Option B:** Cannabis withdrawal symptoms typically include irritability, mood and sleep difficulties, decreased appetite, cravings, restlessness, and a low-grade fever. These symptoms do not match those described in the cases.

**Option C:** Cocaine withdrawal symptoms typically include fatigue, depression, anxiety, irritability, restlessness, and vivid dreams. These symptoms do not match those described in the cases.

**Option D:** Heroin withdrawal symptoms typically include anxiety, agitation, insomnia, sweating, muscle aches, and nausea. These symptoms do not match those described in the cases.

**Option E:** Amphetamine withdrawal symptoms typically include fatigue, depression, anxiety, irritability, restlessness, and vivid dreams. These symptoms do not match those described in the cases, except for one symptom which is the same as case 2.

**Option F:** MDMA withdrawal symptoms typically include fatigue, depression, anxiety, irritability, restlessness, and vivid dreams. These symptoms do not match those described in the cases.

**Option G:** Ketamine withdrawal symptoms typically do not have a clear profile, but may include fatigue, depression, anxiety, irritability, restlessness, and vivid dreams. These symptoms do not match those described in the cases.

**Option H:** LSD withdrawal symptoms typically do not have a clear profile, as LSD is a short-acting substance and withdrawal symptoms are not well-defined. These symptoms do not match those described in the cases.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that withdrawal symptoms can be life-threatening and require prompt medical attention. A thorough history and physical examination, along with laboratory tests, can help diagnose the substance causing withdrawal.

**Correct Answer:** A. Alcohol