Which is the most important group of plants on Earth in terms of ecological and economic significance?

Which of the following have a haploid body in most of the organisms?

Read the given examples carefully: Gelidium,Chara,Spirulina,Chlorella,Fucus,Gracilaria,Polysiphonia,Laminaria,Sargassum,Sphagnum,Dictyota,Ectocarpus. How many of them belong to Red,Brown,and Green algae respectively?

Read the following statements $(A-E)$ and answer the question which follows them.
$(A)$ In liverworts,mosses and ferns,gametophytes are free-living.
$(B)$ Gymnosperms and some ferns are heterosporous.
$(C)$ Sexual reproduction in Fucus,Volvox and Albugo is oogamous.
$(D)$ The sporophyte in liverworts is more elaborate than that in mosses.
$(E)$ Both,Pinus and Marchantia are dioecious.
How many of the above statements are correct?

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

Which of the following characteristics is common to both Gymnosperms and Angiosperms?