## **Core Concept**
The question tests knowledge of viral infections and their characteristic histopathological features, specifically the types of inclusions formed within host cells. Viral inclusions are aggregates of viral particles or proteins that can be found within the nucleus (intranuclear) or cytoplasm (intracytoplasmic) of infected cells.

## **Why the Correct Answer is Right**
The correct answer, **Measles**, is associated with both intranuclear and intracytoplasmic inclusions. In measles virus infection, especially in the context of subacute sclerosing panencephalitis (SSPE), characteristic intranuclear inclusions known as **Cowdry Type A** inclusions can be observed. Additionally, measles virus-infected cells can contain intracytoplasmic inclusions.

## **Why Each Wrong Option is Incorrect**
- **Option A: HSV (Herpes Simplex Virus)**: Primarily known for producing **intranuclear** inclusions (Cowdry Type A), which are characteristic but not typically associated with intracytoplasmic inclusions.
- **Option B: CMV (Cytomegalovirus)**: Characterized by large **intranuclear** inclusions (often referred to as "owl's eye" appearance) but not typically associated with significant intracytoplasmic inclusions.
- **Option D: Rabies**: Known for producing **intracytoplasmic** inclusions called **Negri bodies**, but not characteristically associated with intranuclear inclusions.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that measles virus infection can lead to the formation of both intranuclear and intracytoplasmic inclusions, which is a distinctive feature among viral infections. This is particularly relevant in the context of SSPE, a rare but serious complication of measles infection.

## **Correct Answer:** .