In relation to hypothyroidism, which of the listed symptoms is commonly associated with infants?

Infants with hypothyroidism often present with specific symptoms due to the insufficient production of thyroid hormones that are critical for growth and development. One of the hallmark signs in infants is the presence of a protruding tongue, which can occur because of the accumulation of mucopolysaccharides and is often associated with a characteristic appearance of the infant. Additionally, poor feeding is common as infants might exhibit lethargy or low energy levels, making them less active and less likely to feed adequately.

Thus, the combination of a protruding tongue and poor feeding is specifically indicative of congenital hypothyroidism, which can lead to significant developmental issues if not identified and treated early. The other symptoms associated with the other options do not align with the characteristics of hypothyroidism in infants, such as weight loss or hyperactivity, which are not typical presentations in this population.