Mosses and ferns are

What is common among $Porphyra$,$Agaricus$,$Chlorella$,and $Spirulina$?

Read carefully the following statements:
$I.$ Funaria possesses unicellular and unbranched rhizoids.
$II.$ Gemmae are asexual buds, which originate from small receptacles called gemma cups.
$III.$ The Sphagnum plants have a magnificent property of retaining water.
$IV.$ Mosses along with lichens are the first organisms to colonise rocks.
Which of the statements given above are correct?

Cycas and Adiantum resemble each other in having:

Both gymnosperms and angiosperms bear seeds,then why are they classified separately?

Heterospory and seed formation are usually discussed in the context of which structure?