$Pteridium$ possesses:

In some of the pteridophytes and gymnosperms,the sporophylls aggregate at the apices of the main stem or its branches to form definite compact structures. These compact structures are called:

Photosynthetic sporophylls are found in . . . . . . .

Which of the following is an inconsistent option regarding asexual reproduction in Pteridophytes?

Spores of $Dryopteris$ are

In which one of the following species of $Selaginella$,the apex continues its vegetative growth beyond the formation of $strobilus$?