**Core Concept:** Congenital cataract refers to the development of cataract during fetal life or early infancy. It may be due to various genetic, infectious, or nutritional causes. The primary concern in treating congenital cataract is to restore vision in the affected child.

**Why the Correct Answer is Right:**
Option C (Pfeiffer syndrome) is the correct answer because Pfeiffer syndrome is a rare genetic disorder characterized by abnormal bone growth, which can lead to the development of congenital cataracts. In this case, the cataracts form during fetal life due to the genetic defect.

**Why Each Wrong Option is Incorrect:**
Option A (Down syndrome) is incorrect because Down syndrome is also a genetic disorder, but the cataracts associated with it typically develop later in life, not in infancy.

Option B (Vitamin A deficiency) is incorrect because congenital cataracts due to vitamin A deficiency usually present in early childhood rather than infancy. Vitamin A deficiency cataracts are also typically bilateral (occurring in both eyes), while Pfeiffer syndrome-associated cataracts are usually unilateral (occurring in only one eye).

Option D (Hyperprolactinemia) is incorrect because hyperprolactinemia is a condition characterized by high prolactin levels, which can lead to the development of secondary cataracts in adults. Congenital cataracts are not directly caused by hyperprolactinemia.

**Clinical Pearl:** It is essential to consider genetic disorders like Pfeiffer syndrome when evaluating infants with congenital cataracts, as early diagnosis and intervention can prevent vision loss and improve the child's quality of life.

**Correct Answer:** C. Pfeiffer syndrome