SET-A	SET-B
1) e	A) Covalent radius
2) r	B) Charge of an electron
3) ${\text{Z}}_{\text{eff}}$	C) Effective nuclear charge
	D) Atomic number

For  e represents the charge of an electron.

Covalent radii is used for non-metals, it represents ‘r’

Effective nuclear charge is represented by ${\text{Z}}^{\text{*}}{\text{/Z}}_{\text{eff}}$ it is the net positive  charge experienced by

electron in a multi electron atom.