## **Core Concept**
The question describes a congenital infection caused by an enveloped virus with double-stranded DNA, presenting with symptoms such as petechiae, hepatosplenomegaly, jaundice, and brain calcifications in a newborn. This clinical picture is suggestive of a congenital viral infection, specifically one that affects multiple systems and causes significant morbidity.

## **Why the Correct Answer is Right**
The correct answer, **Cytomegalovirus (CMV)**, is an enveloped virus containing double-stranded DNA. CMV infection is a well-known cause of congenital infection, leading to a range of clinical manifestations including petechiae, hepatosplenomegaly, jaundice, and notably, brain calcifications. CMV is a leading cause of congenital viral infections worldwide and can result in significant long-term sequelae, including hearing loss, developmental delay, and vision impairment.

## **Why Each Wrong Option is Incorrect**
- **Option A: Rubella**, while it can cause congenital infection, typically does not present with brain calcifications. The classic features of congenital rubella syndrome include cataracts, heart defects, and hearing loss, but the specific combination of symptoms and findings like brain calcifications makes CMV a more likely candidate.
- **Option B: Varicella-Zoster Virus (VZV)**, causes chickenpox and shingles. While congenital varicella syndrome can occur, it is less common and usually presents with different features such as limb abnormalities, eye abnormalities, and skin lesions, rather than the combination described.
- **Option D: Parvovirus B19**, primarily causes Fifth disease (erythema infectiosum) and, in the setting of congenital infection, can lead to hydrops fetalis. However, it does not typically cause the specific constellation of symptoms and findings like brain calcifications as commonly seen with CMV.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that **Cytomegalovirus (CMV) infection** is a major cause of congenital infection and can lead to severe long-term disabilities. The presence of **brain calcifications** on imaging in a newborn with a congenital infection is particularly suggestive of CMV. Prevention strategies, including screening for CMV immunity in pregnant women and avoiding exposure, are critical.

## **Correct Answer:** C. Cytomegalovirus (CMV).