What concept explains why drivers are slower to detect traffic signals when talking on a cell phone?

The correct answer is that the concept of divided attention explains why drivers are slower to detect traffic signals when talking on a cell phone. Divided attention refers to the cognitive ability to distribute one's focus across multiple tasks or stimuli simultaneously. When a driver is engaged in a conversation on a cell phone, their attention is split between the conversation and the external environment, which includes monitoring traffic signals and other road conditions.

This split in attention can lead to slower reaction times and diminished awareness of important visual cues, which in this case means that the driver may not notice traffic signals right away. While selective attention involves focusing on a particular stimulus while ignoring others, it doesn't fully capture the essence of managing multiple tasks, as in the case of driving and talking at the same time.

Inattentional blindness, on the other hand, occurs when individuals do not see an unexpected stimulus in their field of view because their attention is engaged on another task. Although this concept is related, it specifically refers to a failure to notice an unexpected stimulus rather than the broader challenge of sharing attention between two concurrent tasks.

Visual processing is more about the brain's ability to interpret visual information but does not directly relate to the distribution of attention between tasks. Thus, divided attention is the most suitable explanation