Which congenital anomaly is defined as a blockage between the nose and pharynx?

Choanal atresia is defined as a blockage between the nose and pharynx, which is a congenital anomaly that can lead to significant respiratory distress in neonates. In this condition, the back of the nasal passage is obstructed, either unilaterally or bilaterally, preventing air from passing through the nasal cavity into the throat. This can result in difficulty breathing, especially when the infant is at rest or feeding, as they rely heavily on nasal breathing at this early stage of life. Infants with complete bilateral choanal atresia may be unable to breathe comfortably and may require immediate medical intervention to ensure adequate airway patency.

In contrast, the other options refer to different congenital conditions. Trisomy 21, also known as Down syndrome, is a chromosomal abnormality that presents with a variety of physical and developmental challenges but is not characterized by a specific airway blockage. Spina bifida is a neural tube defect that affects spinal development and does not involve the nasal passages. Congenital diaphragmatic hernia is a defect in the diaphragm that allows abdominal contents to move into the thoracic cavity, which can compromise lung development and function but does not relate to the blockage of the nasal passage. Understanding choanal at