Arrange the orbitals of H-atom in the increasing order of their energy:
$3{\mathrm{p}}_{\mathrm{x}},2\mathrm{s},4{\mathrm{d}}_{\mathrm{xy}},3\mathrm{s},4{\mathrm{p}}_{\mathrm{z}},3{\mathrm{p}}_{\mathrm{y}},4\mathrm{s}$

For single electron or H-atom energy of orbital is decided only by principle quantum number (n) i.e number of shell orbitals present in the same number of shell will here equal energy. Therefore, the correct answer is option 1

2s<3s=3p_x​=3p_y​<4s=4p_z​=4d_xy​