(h) Bohr stated that the energy of the electron is quantised. What does this mean?

Explanation:

It suggests that the extranuclear part consists of electrons in specific spherical orbits around the nucleus.

The concept is based on the premise that the electrons move round the nucleus in certain permissible orbits or energy levels. The ground state is the lowest energy state available to the electrons. It is the most stable state. The excited state is any higher energy level than the ground state. An electron in an energy level has a definite amount of energy associated with it at that level. The electron can undergo transitions from one level to another. This way energy of an electron is quantized to each level.

Ithink the answer is a or d.