Pain sensation:

Correct Answer: B

Rationale: Pain perception occurs in the cortex, not hypothalamic nuclei (B is incorrect as stated, but none fully fit). Pain is a protective sign (A is subjective), fast pain is carried by A-delta fibers (not C-fibers, ruling out C), and referred pain is typically visceral to somatic (not somatic to visceral, ruling out D). No fully correct option exists; B is closest if reinterpreted as cortical perception.

Correct Answer: C

Rationale: Midbrain reflexes include the hopping reaction (C) and placing reaction, adjusting limb position. Stretch reflex (A) is spinal, tonic neck reflex (B) is medullary/spinal, and positive supporting (D) is medullary. C is correct.

Correct Answer: D

Rationale: Dorsal columns carry vibration (D, correct), position, and fine touch, not crude touch (A, spinothalamic), temperature (B, spinothalamic), or pain (C, spinothalamic). D is correct.

Correct Answer: C

Rationale: Alpha waves are occipital (not temporal, A), beta waves are fast (not slow, B), theta waves are 4-7 Hz (C, correct), and EEG aids but isn’t 100% diagnostic (D). C is correct.

Correct Answer: B

Rationale: The embryonic brain forms three primary vesicles: prosencephalon, mesencephalon, and rhombencephalon. The prosencephalon divides into telencephalon and diencephalon, and the rhombencephalon into metencephalon and myelencephalon. The mesencephalon (B) remains undivided as the midbrain. B is correct.