Identify the stages $A$ and $B$; and what is the correct labelling of $C$ and $D$ in the process of human embryonic development?

• A
  $A$: Morula,$B$: Blastocyst,$C$: Follicular cells,$D$: Inner cell mass
• B
  $A$: Morula,$B$: Blastocyst,$C$: Embryoblast,$D$: Trophoblast
• C
  $A$: Morula,$B$: Blastocyst,$C$: Trophoblast,$D$: Inner cell mass
• D
  $A$: Blastocyst,$B$: Morula,$C$: Trophoblast,$D$: Inner cell mass