The major product in the following reaction is:

Two monomers in maltose are :

White Phosphorus on reaction with concentrated NaOH solution in an inert atmosphere of CO₂ gives phosphine and compound (X). (X) on acidification with HCl gives compound (Y). The basicity of compound (Y) is :

Hydrogen has three isotopes (A), (B) and (C). If the number of neutron(s) in (A), (B) and (C) respectively, are (x), (y) and (z), the sum of (x), (y) an (z) is :