Correct Answer: B

Rationale: Upright positioning is the optimal intervention to promote maximum chest expansion in a child with Duchenne muscular dystrophy. By placing the child in an upright position, gravity can assist in expanding the chest cavity, facilitating better lung expansion and improving breathing efficiency. Deep-breathing exercises may be beneficial but are not as effective in maximizing chest expansion as upright positioning. Coughing and chest percussion focus more on airway clearance and are not directly aimed at promoting chest expansion.

Correct Answer: A

Rationale: The correct answer is 'On the back, lying flat.' Placing infants on their back to sleep is recommended to reduce the risk of sudden infant death syndrome (SIDS). This position promotes safe sleep practices and helps prevent accidental suffocation. Choices B, C, and D are incorrect as placing infants on their side or with the head slightly elevated may increase the risk of breathing difficulties or other hazards during sleep.

Correct Answer: C

Rationale: The correct answer is C: 37% to 47%. The normal hematocrit range for a 12-month-old infant is between 37% to 47%, which reflects the expected blood volume and red blood cell levels for this age. Choice A (19% to 32%) and Choice B (29% to 41%) are too low and do not encompass the typical hematocrit range for a healthy 1-year-old. Choice D (42% to 69%) is too high and falls outside the usual hematocrit values for this age group.

Correct Answer: D

Rationale: The correct priority nursing action in this situation is to administer the prescribed dose of rapid-acting insulin. Rapid-acting insulin is necessary to help lower the elevated blood glucose level quickly, thereby preventing potential complications of hyperglycemia. Encouraging exercise, obtaining a glucometer reading, or suggesting consumption of complex carbohydrates like cheese may not address the immediate need to bring down the high blood glucose level effectively. Exercise could potentially raise blood glucose levels, obtaining a glucometer reading may delay necessary treatment, and consuming complex carbohydrates can further elevate blood glucose levels in this scenario.

Correct Answer: C

Rationale: Tetralogy of Fallot is characterized by a combination of four specific cardiac defects: right ventricular hypertrophy, ventricular septal defect, pulmonic stenosis, and overriding aorta. Choice A is incorrect as it includes mitral valve stenosis, which is not typically part of tetralogy of Fallot. Choice B describes transposition of the great arteries rather than tetralogy of Fallot. Choice D includes an atrial septal defect, which is not part of the classic presentation of tetralogy of Fallot.