Which of the following helps in coal formation?

Which of the following is considered significant in the process of seed development?

What type of spores are produced by the plant shown in the given figure?

$A$: $Selaginella$ is heterosporous.
$R$: The strobili of $Selaginella$ are unisexual.

The first plants to appear after a forest fire are the ferns. This is because of the survival of their:

Read carefully the following statements about sexual reproduction in ferns:
$I.$ Water is essential for fertilization.
$II.$ The male gametophyte bears antheridia,while the female gametophyte bears archegonia,which produce antherozoids and egg cells,respectively.
$III.$ Antherozoids and egg cells fuse to give rise to a zygote. The zygote develops into a young embryo. The embryo gives rise to a sporophyte.
Which of the statements given above are correct?