One character common for $Selaginella$ and fern is

What is the number of chromosomes in each cell of the root of Ophioglossum?

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:

$A:$ In Pteridophytes,spores are produced in sporangia. $R:$ In Pteridophytes,sporangia are subtended by leaf-like appendages called sporophylls.

To which group does the plant shown in the given figure belong?

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