Holding inconsistent models at the same time
For the first excited states,
there are two possibilities: one is that region III is where the greatest potential and so it is the most attractive point for the electron. But I also want to say that region II is where the speed of the electron is at the least. It spends most time there .... I am not sure
. OK. Your probability is the amplitude square of the wavefunction so will be greatest in III.