Amorphous boron is extracted from borax by the following steps :
`"Borax" overset((A))rarr H_(3) BO_(3) overset("Heat")rarr B_(2) O_(3) overset((B)) rarr "Boron" (A) and (B) are`
(a) `H_(2) SO_(4), Al`
(b) `HCl`, Carbon
( c) `H_(2) SO_(4), Mg`
(d) `HCl, Fe`.
A. `H_(2)SO_(4),Al`
B. `HCl`,carbon
C. `H_(2)SO_(4),Mg`
D. `HCl,Fe`