The product obtained in the final step of the following reaction is?

                           ${\mathrm{CH}}_3-{\mathrm{CCl}}_2 -{\mathrm{CH}}_2-{\mathrm{CH}}_3 \underset{∆}{\overset{\mathrm{Alc} \mathrm{KOH}}{\to }}\underset{ }{\overset{\mathrm{Na}/\mathrm{Liq} {\mathrm{NH}}_3}{\to }}\mathrm{product}$

 

• A

  

• B

  

• C

  

• D