Plant Reproduction and Germination

Orthodox seeds are seeds which will survive drying or freezing during ex-situ conservation. There is variation in the ability of orthodox seeds to withstand drying and storage with some seeds being more sensitive than others. Thus, some seeds are considered intermediate in their storage capability while others are fully orthodox.
Thus, the correct answer is option B.

In hypogeal germination, cotyledons remain underground and plumule is elongated above the ground. 
Hypocotyl is part of the stem situated below the cotyledons. If hypocotyl is the active region, then it will elongate and will bring cotyledons above the ground. But, as stated above cotyledons remain underground. 
Radicle gives rise to primary root during germination process. 
Tigellum is the main axis of embryo which protrudes out of the cotyledons and forms radicle and plumule during germination process. 
Epicotyl is part of the stem above cotyledons. During germination process, epicotyl being the active region elongates and pushes plumule above the ground and cotyledons remain underground.
Thus, the correct answer is option B.

The seeds of Abrus precatorius are much valued in native jewelry for their bright coloration. Most beans are black and red, suggesting a ladybug, though other colors are available. Jewelry-making with jequirity seeds is dangerous and there have been cases of death by a finger-prick while boring the seeds for beadwork. The seeds were traditionally used to weigh jewellery in India. Seeds of Xanthium, Calotropis and Thespesia are not used as jeweler's weight. 
Therefore, the correct answer is option B.

Seed is the ripened ovule or mature integumented megasporangium in which outer integument convert into testa and inner integument are grown up as tegmen and after fertilization, the embryo is placed inside seed in dormant state and grow into a new plant in favorable condition.

Endosperm develops after the formation of embryo. It functions as the nutritive tissue for the growing embryo. The endosperm is found as liquid (coconut water) and solid (coconut kernel, white fluffy part of maize). The endosperm found in maize is of nuclear type. 

In the case of coconut plant, the hard shell forms the inner layer of fruit (endocarp). Inside the shell, there is a seed which is covered by a seed coat. This seed coat is brown in colour and attached to the kernel which is endosperm. The seed coat is a thin layer which is protective in nature. 

Water lotus (Nelumbo  nucifera) have an unusually long period of viable germination. Even if, a seed is in the ideal condition of germination, it might remain dormant for decades. They show self-preservation and resistance to germination. 

Plumed seeds occur in Calotropis. The seeds are compressed, broadly ovoid, with a tufted micropylar coma of long silky hair. The crown of the hair on the seeds favouring anemochory give the plumed appearance.

Nelumbo nucifera, also known as Indian lotus, sacred lotus, bean of India, or simply lotus, is one of two species of aquatic plant in the family Nelumbonaceae. This plant is an aquatic perennial. Under favourable circumstances, its seeds may remain viable for many years, with the oldest recorded lotus germination being from that of seeds 1,300 years old recovered from a dry lake bed. 

Many seeds are insensitive to light, but in a number of species, germination is stimulated or inhibited by exposure to continuous or short periods of illumination. So stimulated are many grasses, lettuce, fireweed, peppergrass, mullein, evening primrose, yellow dock, loosestrife, and Chinese lantern plant. Corn, the smaller cereals, and many legumes, such as beans and clover, germinate as well in light as in darkness.
Inhibition by light is found in chive, garlic, and several other species of the lily family, jimsonweed, fennel flower. Sometimes, imbibed (wet) seeds that do not germinate at all in darkness may be fully promoted by only a few seconds or minutes of exposure to white light or to karrikin. The best-studied case of this type, and one that is a milestone in plant physiology, concerns seeds of the Grand Rapids variety of lettuce, which is stimulated to germination by red light (wavelength about 660 nanometres) but inhibited by far-red light (wavelength about 730 nanometres). Red light inhibits stem elongation and lateral root formation but stimulates leaf expansion, chloroplast development, red flower coloration, and spore germination. Such stimulation by red light can be reversed by exposure to far-red light. So, red light is most effective in seed germination compared to green, blue and far red light. 
Therefore, the correct answer is option C.

Tetrazolium salt stains all living tissue in the seed embryo red. Thus, enabling trained analysts to determine the seeds viability or otherwise. The tetrazolium test is used to give a quick estimate of germination potential. The result of a tetrazolium test will generally predict the germination test result closely, however the tetrazolium test will not detect certain types of abnormalities nor will it give any indication of disease levels, chemical damage or dormancy. The viability of a seed is tested by tetrazolium salts. The viable seeds when respire reduce the colourless tetradyes into highly coloured compounds, i.e. 2, 3, 5 triphenyltetrazolium chloride is reduced to triphenylformazon which is red in colour. 
Therefore, the correct answer is option B.