Question

¿Cuál de los siguientes mandatos negativos no está escrito correctamente? No caces. No caes. No toques.

Answer 1

No caes.
That literally means "you do not fall" (as if describing an object that defies the laws of gravity).

The correct way of making it imperative would be, "No caigas", which means "do not fall" (as if telling someone not to fall).