You are driving to school when suddenly an ambulance rushes past you with its sirens blaring, shocking you so much that you fear that you might lose control of your car. A minute later, you hear sirens in the distance and increase your vigilance to be prepared for another emergency vehicle on the road. What change has come over your normal reaction to sirens?

SENSITISATION.

Explanation: SENSITISATION can be defined as the process of reacting to a stimulus in a sensitive manner. In SENSITISATION, the repeated administration of a stimulus results in the progressive amplification of a response.

The siren happening the second time is a repeated stimulus hence prompting the individual to be more vigilant when they hear another siren i.e progressive amplification of a response.

because the early people found out about it.

answer; pentagon papers, vietnam draft-resistor, james dean, american revolution;