A nurse is assisting in the care of a client who is experiencing excessive anxiety and worry in response to a variety of circumstances, and is unable to control their sense of worry. The nurse should identity that these manifestations indicate which of the following?

Choice A reason: Panic disorder is characterized by recurrent, unexpected panic attacks, which are sudden surges of intense fear or discomfort. It is not defined by a "variety of circumstances" or constant worry, but rather by the acute physiological "fight or flight" response and the subsequent fear of future attacks. Choice B reason: Generalized anxiety disorder (GAD) is defined by the DSM-5 as excessive anxiety and worry about a number of events or activities (such as work or school performance) for at least 6 months. The client’s inability to control this pervasive worry is the hallmark feature of GAD. Choice C reason: Separation anxiety disorder involves excessive fear or anxiety concerning separation from those to whom the individual is attached. While it involves worry, the worry is specific to the loss of or harm to attachment figures, rather than a broad spectrum of various life circumstances. Choice D reason: Agoraphobia is a disorder where an individual fears or avoids places or situations that might cause them to feel trapped, helpless, or embarrassed. This is a situational anxiety related to the environment and safety, not the generalized, free-floating worry that permeates different aspects of daily life.