Final answer:
People who are unresponsive are not alert and are unaware of their surroundings. On the other hand, people who are reactive are alert and aware that they are giving responses. The least reactive people in the world are those in deep comas, as they are not able to respond to stimuli or interact with the environment.
Step-by-step explanation:
The correct answer to the question is: People who are reactive are alert and aware they've giving responses. The least reactive people in the world are people in deep comas.
Being reactive means responding to stimuli in the environment, such as answering questions or moving away from something hot. In contrast, someone who is in a deep coma does not exhibit these reactive behaviors, which is why they are described as unresponsive or the least reactive.