Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: Energy of $$2 \mathrm{s}$$ orbital of hydrogen atom is greater than that of $$2 \mathrm{s}$$ orbital of lithium.

Reason R: Energies of the orbitals in the same subshell decrease with increase in the atomic number.

In the light of the above statements, choose the correct answer from the options given below.

Which of the following sets of quantum numbers is not allowed?

The number of radial nodes and total number of nodes in 4p orbital respectively are :

Which of the following is the correct plot for the probability density $${\psi ^2}$$ (r) as a function of distance 'r' of the electron from the nucleus for 2s orbital?