The thickened pyloric muscle causes partial or near-complete gastric outlet obstruction. The infant loses gastric hydrochloric acid through repeated vomiting. With ongoing vomiting, dehydration and electrolyte imbalance can develop. The classic laboratory pattern is hypochloremic, hypokalemic metabolic alkalosis. For NCLEX-RN (Canada), items rarely announce the topic in the first sentence. Anchor to objective data, trajectory, and the safest next step for the role named in the stem before distractors compete. On the exam, writers often pair stable-sounding options with unstable data—notice the mismatch before you commit. If the stem names a license or role, reread that line; scope errors are classic trap answers even when the clinical topic is familiar. Run a 60-second scan: breathing work and oxygenation, perfusion and end organs, neuro baseline, likely infection sources, and devices that can fail quietly. When two answers feel partly right, pick the one that reduces imminent harm and matches orders for the role you were given. Train yourself to state the primary risk in one short phrase before you read the options so distractors do not rewrite your priority list. On...