# What facts are being used in this atomic structure question?

I wish to understand how to solve this atomic structure question:

For the ground state, the electron in the H-atom has an angular momentum = $\hslash$ , according to the simple Bohr model. Angular momentum is a vector and hence there will be infinitely many orbits with the vector pointing in all possible directions. In actuality, this is not true, because:

1. Bohr model gives incorrect values of angular momentum.
2. only one of these would have a minimum energy.
3. angular momentum must be in the direction of spin of electron.
4. electrons go around only in horizontal orbits.

Actually, we have been taught Bohr orbits a lot in class, with formulae for everything (atomic radius/electron orbital speed/various energy levels/etc.) and also basics of the quantum mechanical model. However, we didn't go into such a great depth of Bohr orbits as asked in the above question.

Specifically, I don't know of any reasonable arguments against points 1,2,3. Point 4 is evidently wrong based on the quantum mech model.

How do I develop any claim for/against the points 1,2,3? What are the facts involved here?