The homologue of Ethyne can be prepared from 

• A

  ${\text{Al}}_{\text{4}}{\text{C}}_{\text{3}}{\text{ + H}}_{\text{2}}\text{O}\underset{ }{\overset{ }{\to }}$

• B

  ${\text{CaC}}_{\text{2}}{\text{ + H}}_{\text{2}}\text{O}\underset{ }{\overset{ }{\to }}$

• C

  ${\text{Mg}}_{\text{2}}{\text{C}}_{\text{3}}{\text{ + H}}_{\text{2}}\text{O}\underset{ }{\overset{ }{\to }}$

• D

  ${\text{Be}}_{\text{2}}{\text{C}}_{ }{\text{ + H}}_{\text{2}}\text{O}\underset{ }{\overset{ }{\to }}$