Elizabeth always seems to feel on edge, and worried that something in her life will go wrong, but she cannot pinpoint the cause of her anxiety. these symptoms can be best classified as

The correct answer is Generalized Anxiety Disorder.

Explanation:

Generalized Anxiety Disorder is a form of anxiety in which a person feel unrealistic anxiety about two or more things of his life. This anxiety could be about the financial conditions of the person, about the relationships, about the health, about the work, etc. This anxiety may cause shortness of breath and palpitations. The person experiencing this disorder doesn't aware of the real cause of his anxiety. So in this case, Elizabeth is always worried that something bad will happen in her life but she is unable to pinpoint the cause. It means, she is suffering from the Generalized Anxiety Disorder.