The usual normal posture of a full term healthy infant is

Correct Answer: B

Rationale: Full-term infants exhibit flexion of lower and upper extremiti, per neonatal norms, due to physiologic flexor tone from corticospinal immaturity. Fencing posture is asymmetrical tonic neck reflex, not resting state. Mixed flexion-extension (C-D) or full extension suggest hypotonia or prematurity. Flexion reflects healthy tone, making B the correct answer.

Correct Answer: C

Rationale: Steppage gait results from common peroneal nerve palsy, per neurology texts, with high stepping to clear the foot due to dorsiflexor weakness (foot drop). Shuffling is parkinsonian; tandem tests balance; toe walking spasticity. Steppagcompensation makes C the correct answer.

Correct Answer: A

Rationale: Axonal neuropathidiminish NCV amplitude, per neurophysiology, from axon loss reducing signal strength. Guillain-Barré slows velocity (demyelination); botulism and myasthenia affect junctions, not amplitude; viral meningitis is unrelated. Axonal pathology makes A the correct answer.

Correct Answer: B

Rationale: MRI is the study of choice for focal deficits, altered consciousness, or chronic headaches, per AAN, due to superior detail of brain parenchyma, ischemia, or masses. CT is faster for acute hemorrhage; X-ray skeletal; EEG seizures; LP infection. MRIs resolution make B the correct answer.

Correct Answer: D

Rationale: Generalized 3-Hz spike-and-wave on EEG indicatabsence seizure , per ILAE, common in childhood absence epilepsy, with brief staring spells. Atypical absence has slower (<2.5 Hz) waves; benign childhood focal spikes; aphasia language loss; West hypsarrhythmia. Classic EEG pattern makes D the correct answer.