Which statement about an ammonium ion is right?
- AAll of the H-N-H bond angles in the ion are $90^{\circ}$.
- BAll of the H-N-H bond angles in the ion are $107^{\circ}$.
- CThe ion contains a N-H dative covalent bond which is weaker than the other three N-H covalent bonds.
- DThe ion will react with a base as it is a weak acid.