Which is the smallest cranial nerve?

Correct Answer: C

Rationale: The trochlear nerve (IV) is the smallest cranial nerve. It innervates the superior oblique muscle, which helps control eye movement.

Correct Answer: B

Rationale: The cervical sympathetic trunk runs lateral to the vertebral artery and posterior to the carotid sheath. It contains ganglia that provide sympathetic innervation to the head and neck.

Correct Answer: D

Rationale: The trochlear nerve (IV) innervates the superior oblique muscle, which depresses and abducts the eye. Paralysis of this nerve prevents downward gaze when the eye is turned inward.

Correct Answer: C

Rationale: The S1 and S2 nerve roots innervate the gastrocnemius and soleus muscles, which are responsible for plantar flexion of the ankle. This is important in assessing sacral nerve root function.

Correct Answer: B

Rationale: Dementia is an umbrella term for a group of conditions characterized by a decline in cognitive function, including memory loss, impaired reasoning, and changes in behavior. Alzheimer's disease is the most common form of dementia, but other types include vascular dementia and Lewy body dementia.