What is required for fertilization in the plant shown in the given figure?

The first evolution of the seed habit occurred in which of the following?

The prothallus of fern is

From an evolutionary point of view,the retention of the female gametophyte with the developing young embryo on the parent sporophyte for some time is first observed in:

In pteridophytes,fusion of gametes takes place in

The number of male prothallial cells in $Selaginella$ is: