Test Joshua greene's neuroscientific explanation

QUESTION 1: What is the key difference between the two Trolley Dilemma scenarios, according to Joshua Greene?

The very strong and visceral emotional response against the idea of directly causing harm to another person
The rational justification for saving the greatest number of people
Activation of brain areas related to calculation
The decision not to pull the lever in the first scenario

That in both scenarios the same areas of the brain are activated equally
That the pushing scenario activates the emotional areas more, and the lever scenario activates the reasoning areas more
That the brain does not distinguish between the two scenarios
That the "yuk factor" has no neurological basis