What is the correct sequence for the formation of an embryo sac?

• A
  Nucellar cell $\rightarrow$ Megasporangium $\rightarrow$ Megaspore mother cell $\rightarrow$ Megaspore $\rightarrow$ Embryo sac
• B
  Nucellar cell $\rightarrow$ Megaspore $\rightarrow$ Megaspore mother cell $\rightarrow$ Embryo sac
• C
  Nucellar cell $\rightarrow$ Megaspore mother cell $\rightarrow$ Megaspore $\rightarrow$ Embryo sac
• D
  None of the above