Which of the following terms relates to the swelling of an infant's scalp?

Caput succedaneum refers to the swelling that occurs on an infant's scalp, typically as a result of the pressure exerted by the mother's pelvic bones during delivery. This condition is characterized by edema and is usually soft and diffuse, covering the entire head or a large part of it, and it crosses suture lines, which distinguishes it from other conditions.

The swelling happens because of the accumulation of fluid, and it is generally a benign condition that resolves itself within a few days after birth. It is often seen in infants who experience prolonged labor or when there is a use of forceps during delivery.

In contrast, a cephalhematoma is a collection of blood between the skull and the periosteum and does not typically cross suture lines. Ventriculomegaly refers to an enlargement of the brain's ventricles, indicating potential neurological issues, while microcephaly is a condition where the head is smaller than expected due to a variety of causes, often related to brain development issues. Therefore, caput succedaneum is the specific term that accurately describes the soft swelling found on an infant's scalp after birth.