There are---------- layers of meninges around the brain and spinal cord.

Correct Answer: C

Rationale: Three layers of meninges (dura mater, arachnoid mater, pia mater) surround and protect the brain and spinal cord.

Correct Answer: C

Rationale: The brain stem comprises the midbrain, pons, and medulla oblongata, regulating vital functions.

Correct Answer: D

Rationale: Sobriety tests assess coordination and balance, functions of the cerebellum, which is impaired by alcohol.

Correct Answer: D

Rationale: The fovea is cone-dominated (few rods), periphery is rod-rich; the photoreceptor-to-RGC ratio is high in the periphery due to convergence.

Correct Answer: B

Rationale: Inner hair cells (fewer in number) are the primary sensory transducers, sending most input to the auditory nerve via spiral ganglion cells.