Acetylene on acidic hydrolysis in presence of $HgS{O}_4$ gives aldehyde 

$\underset{\mathrm{Acetylene}}{\mathrm{CH}\equiv \mathrm{CH}} \underset{{\mathrm{HgSO}}_{4(\mathrm{aq}.)}}{\overset{{\mathrm{H}}_2{\mathrm{SO}}_4}{\to }} \underset{ \mathrm{Acetaldehyde} }{{\mathrm{CH}}_3\mathrm{CHO}}$ 

Acetaldehyde when treated with Potassium dichromate in acidic condition gives carboxylic acid 

${\mathrm{CH}}_3\mathrm{CHO} \underset{{\mathrm{K}}_2{\mathrm{Cr}}_2{\mathrm{O}}_7}{\overset{{\mathrm{H}}_2{\mathrm{SO}}_4}{\to }} \underset{\mathrm{Acetic} \mathrm{acid} }{{\mathrm{CH}}_3\mathrm{COOH}}$ 

Acetic acid when treated with Calcium hydroxide it gives calcium derivative of carboxylic acid. 

${\mathrm{CH}}_3\mathrm{COOH}\stackrel{\mathrm{Ca}{\left(\mathrm{OH}\right)}_2}{\to }\underset{\mathrm{Calcium} \mathrm{Acetate}}{{\left({\mathrm{CH}}_3\mathrm{COO}\right)}_2\mathrm{Ca}}$

 Calcium acetate on heating in air gives Propanone. 

${\left({\mathrm{CH}}_3\mathrm{COO}\right)}_2\mathrm{Ca}\stackrel{▵}{\to }\underset{\mathrm{Propanone} }{{\mathrm{CH}}_3{\mathrm{COCH}}_3}$

Hence, the correct answer is option (B) Propanone.