Botany and Plant Science

Mosses are non-vascular plants, meaning they lack true vascular tissues like xylem and phloem. Instead, conduction of water and nutrients is carried out by specialized elongated parenchymatous cells called hydroids (for water) and leptoids (for food), which are structurally simple parenchyma.

Riccia is a bryophyte, a group in which the dominant, independent phase of the life cycle is the gametophyte, which produces haploid gametes. In Lycopodium, Equisetum, and Pinus, the dominant plant body is the sporophyte.

The leaf-like structures of moss gametophytes are photosynthetic and contain chloroplasts, but they lack true stomata. Stomata are present on the sporophyte capsule rather than the gametophytic leaves.

Polytrichum is a bryophyte (moss) which exhibits a dominant, independent gametophytic phase alternated by a multicellular sporophyte that is physically dependent on the gametophyte.

In Hepaticopsida (liverworts like Marchantia and Riccia), the rhizoids are unicellular and are of two distinct types: smooth-walled and tuberculate (pegged).

Statements (i), (ii), and (iii) are correct. Statement (iv) is incorrect because the sporophyte in mosses is more elaborate than in liverworts. Statement (v) is incorrect because Pinus is monoecious, while Marchantia is dioecious.

Plant body of bryophyte is differentiated than that of algae and it is thallus like and prostate and effect. The main plant body is haploid and is known as gametophyte. There is a multicellular body which is known as sporophyte which is not free living and is attached to the gametophyte and derives nourishment from it.

Sperm of mosses are biflagellated, ie., it has two flagella that aid in propulsion. Since sperm must swim to the archegonium, fertilisation cannot occur without water.

In Marchantia particularly it appears that only some of the spore mother cells (Sporocytes) which are diploid remain diploid and undergo change to form elaters. 
The other ( Majority of them ) undergo meiosis to form haploid spores. 
So in Marchantia the elaters are diploid. 

Merosity is a term that refers to the number of component parts in each whorl of the plant basically the flowers which include, sepals, petals, and stamens. the trimerous condition is a characteristic feature of monocots and is found in Liliaceae.
Walking fern refers to the species of Asplenium. Adiantum caudatum is walking maidenhair.
The vascular system of gymnosperms is made up of xylem with tracheids, parenchyma, and rays. vessels are however present in Gnetum, Ephedra having evolved from pitted tracheids. The phloem is made up of sieve cells but companion cells are absent.
Riccia and Marchantia are liverworts a belong to  the order Marchantiales. Thus, the correct answer is option E.

A prothallium, or prothallus is usually the gametophyte stage in the life of a fern or other pteridophyte. Occasionally, the term is also used to describe the young gametophyte of a liverwort or peat moss as well. An archegonium is a multicellular structure or organ of the gametophyte phase of certain plants, producing and containing the ovum or female gamete. The corresponding male organ is called as the antheridium. An antheridium or antheridia is a haploid structure or organ producing and containing male gametes (called as antherozoids or sperm). It is present in the gametophyte phase of cryptogams like bryophytes and ferns, and also in the primitive vascular psilotophyta. Rhizoid is a filamentous outgrowth or root hair on the underside of the thallus in some lower plants, especially mosses and liverworts, serving both to anchor the plant and (in terrestrial forms) to conduct water. 

Riccia (a bryophyte), Dryopteris (a pteridophyte), and Cycas (a gymnosperm) all produce motile, flagellated male gametes (antherozoids). In contrast, angiosperms like Calotropis and Hydrilla, and certain algae like Spirogyra, do not have flagellated male gametes.

Dichotomous branching, where the growing point divides into two equal branches, is a characteristic feature of the thalloid liverworts (such as Riccia and Marchantia). Mosses like Funaria and higher vascular plants like Pinus show lateral branching instead.

An immature male gametophyte (pollen grain) consists of a vegetative cell and a generative cell. Upon pollination and germination, the generative cell divides mitotically to produce two male gametes, forming the mature male gametophyte.