**Core Concept**
Psychosis refers to a state of disconnection from reality, characterized by a disorganized thinking process, delusions, hallucinations, and a lack of insight into one's illness. This condition is often associated with severe mental health disorders, such as schizophrenia.

**Why the Correct Answer is Right**
The correct answer will be the feature that is not typically included in the diagnosis of psychosis. This may involve distinguishing between the core symptoms of psychosis and other related but distinct clinical features.

**Why Each Wrong Option is Incorrect**
**Option A:** Disorganized thinking is a hallmark of psychosis, often manifesting as illogical or incoherent speech patterns, disjointed thoughts, and difficulty maintaining a coherent narrative.
**Option B:** Delusions are a fundamental aspect of psychosis, involving fixed, false beliefs that are not amenable to change in light of conflicting evidence.
**Option C:** Hallucinations are also a key feature of psychosis, characterized by perceptions in the absence of external stimuli, which may be auditory, visual, or tactile in nature.

**Clinical Pearl / High-Yield Fact**
A key distinction to make in the context of psychosis is between the primary symptoms (delusions, hallucinations, disorganized thinking) and secondary symptoms (such as depression, anxiety, or social withdrawal), which may co-occur but are not inherent to the condition.

**Correct Answer: D**