Correct Answer: C

Rationale: Low-set ears with lobe creases are often associated with genetic disorders, such as Down syndrome, and can indicate underlying chromosomal abnormalities. This physical characteristic is a common feature seen in various genetic syndromes. The other choices, including feeding problems, weight and height measurements, and motor skills, are not typically specific indicators of genetic disorders in the absence of other associated features.

Correct Answer: B

Rationale: The correct answer is B: Tissue oxygen needs. Polycythemia occurs as the body's response to chronic hypoxia by increasing RBC production to enhance oxygen delivery. In tetralogy of Fallot, a congenital heart defect, the heart's structure causes reduced oxygen levels in the blood. This chronic hypoxia stimulates the bone marrow to produce more red blood cells, leading to an elevated RBC count. Choice A is incorrect as low blood pressure is not directly related to polycythemia in this context. Choice C, diminished iron level, is not the cause of polycythemia in tetralogy of Fallot. Choice D, hypertrophic cardiac muscle, is not the primary cause of the elevated RBC count in this case.

Correct Answer: B

Rationale: The correct answer is B: Paroxysmal abdominal pain. Colic in infants is characterized by paroxysmal abdominal pain, leading to excessive crying and fussiness. It is not caused by inadequate peristalsis (Choice A), an allergic response to certain proteins in milk (Choice C), or a protective mechanism designed to eliminate foreign proteins (Choice D). Understanding that colic is primarily associated with abdominal pain helps healthcare providers provide appropriate care and support to parents dealing with colicky infants.

Correct Answer: B

Rationale: The most important nursing intervention for a child with bronchiolitis is providing respiratory therapy. This intervention helps to maintain airway patency and improve breathing, which are crucial in managing bronchiolitis. Administering bronchodilators (Choice A) may be a part of the treatment plan but is not the most important intervention. Monitoring oxygen saturation (Choice C) is important but falls secondary to providing direct respiratory support. Encouraging fluid intake (Choice D) is also essential but does not address the immediate respiratory needs of the child with bronchiolitis.

Correct Answer: C

Rationale: A spiral fracture is a type of fracture often associated with twisting injuries and can raise suspicion of child abuse. This type of fracture is caused by a twisting force applied to a bone. Plastic deformity is not typically associated with fractures but refers to the ability of a material to change shape and retain that shape. A buckle fracture, also known as a torus fracture, is an incomplete break in a bone commonly seen in children. A greenstick fracture is an incomplete fracture where the bone is bent and partially broken, more commonly seen in children due to their bone flexibility.