You don't fall into the false dichotomy of even entering into playing that game. Your question presents a false dichotomy that (dangerously) is pushing things into trying to institutionalise a justification of killing a fellow human being. Worst, is trying to do that a priori. Is exactly what dictatorships, genocides and Eugenicists would use.
In Nature, and even in urban life, the chances of experiencing the Trolley problem are close to nil.
Nope, you don't understand the trolley problem. It's a very precise tool designed to explore the workings of human conscience. It's a toy problem, not meant to be used with real-world situations. What it shows is that humans indeed have the intuition that, ceteris paribus, the value of lives adds up - saving two lives is more right than saving just one.
