What type of hallucination is most dangerous?

All of the following are examples of acute cerebrovascular emergencies, EXCEPT:

A) embolic blockage of a cerebral artery. B) accumulation of atherosclerotic plaque. C) rupture of a cerebral arterial aneurysm. D) stroke secondary to thrombus rupture.

Generally speaking, the process of image analysis should start with

a. the formulation of a hypothesis as to cause. b. a review of the entire image. c. the identification of patterns or cues. d. the selection of a final hypothesis as to a cause of the problem.