The Eu²⁺ ion is a strong reducing agent in spite of its ground state electronic configuration (outermost) : [Atomic number of Eu = 63]

The structures A and B formed in the following reaction are : [Ph = $$-$$C₆H₅]

In which one of the following sets all species show disproportionation reaction?

Match List - I with List - II

	List - I (Parmeter)		List - II (Unit)
(a)	Cell constant	(i)	$$S\,c{m^2}mo{l^{ - 1}}$$
(b)	Molar conductivity	(ii)	Dimensionless
(c)	Conductivity	(iii)	$${m^{ - 1}}$$
(d)	Degree of dissociation of electrolyte	(iv)	$${\Omega ^{ - 1}}{m^{ - 1}}$$

Choose the most appropriate answer from the options given below :