For the last 2 months Tim has been worried that something bad is going to happen. He cannot pinpoint the source of this feeling, but he is jumpy and irritable and he cannot sleep or concentrate. Which anxiety or mood disorder does Tim have: specific phobia, social anxiety disorder, generalized anxiety disorder, panic disorder, agoraphobia, obsessive-compulsive disorder, posttraumatic stress disorder, major depressive disorder, persistent depressive disorder, bipolar I disorder, or bipolar II disorder? Explain your choice.