Arrange the following in correct order of basicity

Options

A. `I gt II gt III`
B. `III gt II gt I`
C. `II gt I gt III`
D. `I gt III gt II`

Explanation

Hybridisation of N-atom in the compounds given below are `sp^(2), sp^(3)` and `sp^(2)` respectively.

Greater the s-character, more will be electronegativity of N-atom and lesser will be its basicity on this basis, I is less basic than II.
Conjugation If lone pairs of electrons of N are involved in conjugation causes decrease in basicity of compound due to lesser availability of ione pair for donation to show basic nature.

Lone pair involved in formation of aromatic sextet of `6pi`-electron (least basic).