A presumptive sign that would lead the nurse practitioner to suspect pregnancy in an adolescent is:

Rationale:
A. Caput succedaneum is edema of the scalp that crosses suture lines and results from pressure on the presenting part during delivery, not a true hemorrhage.
B. Cephalohematoma is a subperiosteal hemorrhage, meaning blood collects between the periosteum and the skull bone. It is typically firm, well-defined, and does not cross suture lines. It may appear several hours after birth and usually resolves spontaneously over weeks to months.
C. Subdural hemorrhage involves bleeding beneath the dura mater, often associated with trauma or birth complications, but it is deeper than a cephalohematoma and may cause neurological signs.
D. Subarachnoid hemorrhage occurs in the space between the arachnoid and pia mater; it is not limited to the periosteum and is rare in uncomplicated deliveries.

Rationale:
A. Hypocalcemia in infants typically presents with tremors, jitteriness, positive Chvostek or Trousseau signs, and seizures, rather than a shrill cry.
B. A shrill or high-pitched cry is a classic neurologic sign that may indicate increased intracranial pressure (ICP) or central nervous system irritation. Additional signs may include lethargy, irritability, vomiting, and bulging fontanel.
C. Upper airway obstruction usually produces stridor, noisy breathing, or retractions, but not a shrill cry.
D. Vocal cord paralysis may cause a weak, hoarse, or breathy cry, not the high-pitched, shrill cry associated with neurologic issues.