Never ________ on any one thing.

The correct choice emphasizes the importance of maintaining a healthy perspective and balance rather than becoming overly attached to a single idea or task. When someone is advised to never "fixate," it suggests that concentrating too intensely on one thing can lead to missed opportunities or hinder overall progress. By avoiding fixating, individuals can keep their minds open to new possibilities, perspectives, and experiences, which can enhance their decision-making and adaptability.

In contexts such as driving or situational awareness, fixating can be particularly detrimental because it may distract a person from other important aspects of the environment that require attention. This encourages a more holistic approach to tackling challenges or making decisions, promoting versatility and responsiveness.