How does the Expanded Polystyrene (EPS) impact-absorbing liner inside a motorcycle helmet protect the rider's brain during a severe collision?

1. By acting like a high-tension spring that bounces the rider's head back to its original position instantly
2. By absorbing sweat and ventilating engine heat away from the scalp without undergoing physical changes
3. By permanently crushing and deforming microscopically to absorb kinetic energy and extend deceleration time, reducing peak G-forces transferred to the skull
4. By hardening into a rigid solid block upon impact to prevent the outer shell from flexing