**Core Concept**
The 'flash-back' phenomenon is a type of memory distortion that can occur with the use of certain psychoactive substances, particularly those with hallucinogenic properties. This phenomenon is characterized by the recurrence of vivid, intrusive memories of past events, which can be distressing and disrupt daily life.

**Why the Correct Answer is Right**
The 'flash-back' phenomenon is closely associated with the use of lysergic acid diethylamide (LSD), a potent hallucinogenic drug that affects the serotonin system in the brain. LSD binds to serotonin receptors, particularly the 5-HT2A receptor subtype, leading to altered perception, mood, and cognition. The flash-back phenomenon is thought to result from the reactivation of previously stored memories, which are then distorted and relived in a vivid, intrusive manner. This can occur even after the effects of the drug have worn off, and can be triggered by various stimuli, such as sights, sounds, or emotions.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the flash-back phenomenon is not typically associated with the use of benzodiazepines, which are a class of sedatives and anxiolytics that primarily affect the GABA system in the brain.

**Option B:** This option is incorrect because the flash-back phenomenon is not typically associated with the use of opioids, which are a class of drugs that primarily affect the mu opioid receptor and are used for pain relief and anesthesia.

**Option C:** This option is incorrect because the flash-back phenomenon is not typically associated with the use of antipsychotic medications, which are a class of drugs that primarily affect the dopamine system in the brain and are used to treat psychotic disorders such as schizophrenia.

**Clinical Pearl / High-Yield Fact**
It's essential to note that the flash-back phenomenon can occur with other substances, including cannabis and certain types of antidepressants. However, it is most closely associated with the use of LSD and other hallucinogenic drugs. This phenomenon highlights the complex and often unpredictable nature of psychoactive substances, and the need for careful evaluation and management of patients who experience these symptoms.

**Correct Answer: D. LSD**