The diagram shows the entry of a pollen tube into the embryo sac. Identify $A$ to $G$ in the diagram.

• A
  $A-Synergid, B-Filiform apparatus, C-Male gamete, D-Plasma membrane, E-Central cell, F-Egg nucleus, G-Vegetative nucleus$
• B
  $A-Filiform apparatus, B-Central cell, C-Egg nucleus, D-Vegetative nucleus, E-Male gamete, F-Synergid, G-Plasma membrane$
• C
  $A-Plasma membrane, B-Synergid, C-Filiform apparatus, D-Male gamete, E-Vegetative nucleus, F-Central cell, G-Egg nucleus$
• D
  $A-Central cell, B-Egg nucleus, C-Vegetative nucleus, D-Male gamete, E-Synergid, F-Plasma membrane$