A 28-year-old taxi driver is chronically consumed by fears of having accidentally run over a pedestrian. Although he tries to convince himself that his worries are silly, his anxiety continues to mount until he drives back to the scene of the “accident” and proves to himself that nobody lies hurt in the street. What is the most likely diagnosis?

A. obsessive-compulsive disorder

B. obsessive-compulsive personality disorder

C. delusional disorder

D. specific phobia