When the thought required for an action has become routine and instinctive, the performance of the task is described as:

The performance of a task being described as "automatic" refers to a state in which the thought processes required for that action have become so habitual that they no longer require active effort or conscious awareness. This level of performance allows individuals to carry out tasks without needing to consciously think about the steps involved, making the actions more efficient and often faster to execute.

For example, think of driving a car. Experienced drivers can perform intricate maneuvers, such as changing lanes or merging, with little to no conscious thought about each action involved. They have practiced these processes to the point that they become second nature, illustrating the automaticity of certain tasks.

In contrast, the other choices reflect different levels or types of cognitive engagement. "Deliberate" refers to actions taken after careful consideration, requiring conscious thought and decision-making. "Intentional" suggests a purpose behind actions, while "reflected" would imply that the actions are being thought about or analyzed after they've occurred. None of these depict the effortless execution typical of automatic processes.