i.(A) `overset(Delta)to ` glassy traparent beat (B) on platinum wire
(B) `+ CuSO_(4) rarr ` coloured bead(C )
ii `underset((D))((A))+conc. H_(2)SO_(4)+CH_(3)CH_(2)OH overset("ignite")rarr` green flame
iv.Aqueous solution (A) is alkline
Identify A .
A. `NaNH_(4)HPO_(4).4H_(2)O`
B. `NA_(2)B_(4)O_(7).10H_(2)O`
C. `CuSO_(4).SH_(2)O`
D. None of these