Cover the newborn’s eyes with eye shields or patches. This is because phototherapy can cause eye damage and irritation to the newborn, so the eyes should be protected while the lights are on.

Some possible explanations for the other choices are:

• Choice A is wrong because applying sunscreen to the newborn’s skin before placing under the lights can interfere with the effectiveness of phototherapy and increase the risk of skin irritation and infection.

• Choice C is wrong because turning off the phototherapy lights during feedings can reduce the exposure time and delay the clearance of bilirubin from the newborn’s blood.

• Choice D is wrong because keeping the newborn fully clothed to prevent heat loss can also interfere with the effectiveness of phototherapy and increase the risk of overheating and dehydration.

Normal ranges for bilirubin levels in newborns vary depending on the age, gestational age, and risk factors of the newborn. Generally, a total serum bilirubin level of less than 12 mg/dL (205 micromol/L) is considered normal for term newborns in the first week of life. Phototherapy is usually indicated when the total serum bilirubin level exceeds 15 mg/dL (257 micromol/L) for term newborns or 10 mg/dL (171 micromol/L) for preterm newborns.