Consider two chemical reactions (A) and (B) that
take place during metallurgical process:
(A) ${\mathrm{ZnCO}}_{3\left(\mathrm{s}\right)}\stackrel{\mathrm{\Delta }}{⟶}{\mathrm{ZnO}}_{\left(\mathrm{s}\right)}+{\mathrm{CO}}_{2\left(\mathrm{g}\right)}$
(B) $2{\mathrm{ZnS}}_{\left(\mathrm{s}\right)}+3{\mathrm{O}}_{2\left(\mathrm{g}\right)}\stackrel{\mathrm{\Delta }}{⟶}2{\mathrm{ZnO}}_{\left(\mathrm{s}\right)}+2{\mathrm{SO}}_{2\left(\mathrm{g}\right)}$
The correct option of names given to them respectively is:

• Correct answer
  A

  (A) is calcination and (B) is roasting
• B

  Both (A) and (B) are producing same product so both are roasting
• C

  Both (A) and (B) are producing same product so both are calcination
• D

  (A) is roasting and (B) is calcination

Hence, the correct answer is option: 'A'.