Which environmental factor is included in the concept of "client variables"?

The concept of "client variables" encompasses various characteristics that define and influence a client's health and well-being. One critical environmental factor within this concept is age. Age significantly impacts individuals’ health status, risk factors, and responses to treatment. For example, the elderly may have different health concerns and require different care than younger individuals. Additionally, developmental stages associated with different ages can impact health behaviors, disease susceptibility, and the effectiveness of interventions.

While the other options listed—climate, allergic reactions, and insurance status—can indeed affect a client's health, they are not classified as client variables in the same way age is. Climate refers to external environmental conditions, allergic reactions relate to individual responses to specific allergens, and insurance status pertains more to access to healthcare rather than intrinsic client characteristics. Thus, age is the most suitable choice under the category of client variables.