Chelsea Worries Constantly That Her Son Will Be Infected with Germs

Chelsea worries constantly that her son will be infected with germs when someone touches him.She has developed elaborate hand-washing rituals so that she won't infect him,and she will not allow others to hold,talk,or play with him unless she can supervise as they wash their hands with soap.Chelsea is suffering from

A) generalized anxiety disorder.
B) specific phobia.
C) posttraumatic stress disorder.
D) obsessive-compulsive disorder.