Ferns are characterised by

The sperm of fern is

Heterospory and seed habit are exhibited by a plant possessing

Match the following:

Column-$I$ (Classes)	Column-$II$ (Examples)
$A$. Psilotopsida	$I$. Dryopteris,Pteris,Adiantum
$B$. Lycopsida	$II$. Equisetum
$C$. Sphenopsida	$III$. Selaginella
$D$. Pteropsida	$IV$. Lycopodium
	$V$. Psilotum

Heterospory,i.e.,the formation of two types of spores—microspores and megaspores—is a characteristic feature in the life cycle of a few members of pteridophytes and all spermatophytes. Do you think heterospory has some evolutionary significance in the plant kingdom?

If the number of chromosomes in the foot of a fern embryo is $8$,what should be the number of chromosomes in its spores?