Ferns are used:
a. by florists to augment bouquets
b. for medicinal purposes
c. as fertilizers in rice paddies.
d. as food in many different places across the world
e. all of the above are true.

E. All of the above are true.

Explanation:

The fern (Dryopteris filix-mas) is a plant of prehistoric origin and its origin dates back millions of years ago. It is a species widely used as an ornamental plant, medicinal, fertilizer and food and very common in humid tropical environments, usually where there is not much solar incidence.

In folk medicine, fern rhizomes concentrate the main medicinal properties of fern, which has astringent action, anthelmintics (fighting various types of parasitic diseases), febrifuges (reduce fever) and worms (eliminate worms from the body). Its main indications are for the treatment of diseases such as meningitis, pneumonia, measles and worms, especially to eliminate nematelmints and solitary. Externally, the male fern has been used for abscesses, carbuncles, boils and wounds.

In Brazil, especially in the state of Minas Gerais, some restaurants also offer pots or fern sprouts, including Pteridium aquilinum. During preparation, cooks often perform the “seven boils” so that any active ingredients that may be toxic are contained.

Ferns are being widely used in wedding decoration and have also started to appear in bouquets. Florists have been using ferns with a technique to make the bouquet bulkier.

Some regions have also used fern leaves as a natural fertilizer between the rice lines.

answer and explanation;

volcanic rocks are igneous rocks which form from lava, molten rock which has been thrust out of a volcano onto the surface of a rocky body such as an asteroid, planet, or dwarf planet.  

plutonic rocks are igneous rocks which form from subterranean chambers of molten rock or magma. plutonic rocks make up the base of continental crust as well as oceanic crust. their slow rate of formation causes them to be coarse grained since there is plenty of time for large crystals to form before the magma solidifies into rock.

the textural difference is that plutonic rocks are more coarse grained than volcanic rocks. plutonic rocks are coarse grained while volcanic are fine grained ; glassey or fragmental. since fine and coarse are adjectives the decision as to whether a rock is fine or coarse grained is generally made on the bases of whether or not the individual crystals can be seen in most if the rock.