Which of the following is referred to as "ugly" stress?

The term "ugly" stress typically refers to stress that is perceived negatively and has detrimental effects on an individual's well-being. Mental and poor physical exercise can lead to feelings of frustration, burnout, and a host of negative emotional and physical responses. This kind of stress contrasts with positive exercise stress, which can motivate and energize individuals and improve their overall health.

In this context, when someone engages in mental exercise or inadequate physical exercise without proper technique or enjoyment, it may lead to feelings of failure, anxiety, or physical discomfort, which collectively embody the concept of "ugly" stress. This type of stress does not contribute positively to mental or physical health and can hinder performance or motivation. Thus, it aligns well with the definition of stress that is undesirable and harmful, validating the selection of this answer.