Read the following statements 

a) Heterosporous condition. 

b) Female gametophyte in these plants are retained on parent sporophytes for variable periods.

c) The development of the zygote into young embryo takes place within the female gametophytes.

These events are related to 

• A

  Lycopodium

• B

  Selaginella

• C

  Adiantum

• D

  Polytrichum