A 28-year-old man from Mumbai presents with a 3-year history of intense, irrational fear of dogs. He reports that whenever he encounters a dog—even from a distance or in photographs—he experiences immediate anxiety, rapid heartbeat, and an overwhelming urge to escape. He has restructured his daily life to avoid parks, streets where dogs are common, and friends' homes with pets. He recognizes his fear is excessive but feels unable to control it. He denies panic attacks between exposures, and his anxiety is specifically triggered by dogs, not other situations. What is the most likely diagnosis?