Transgenic plants are obtained by genetic engineering.
e.g. like Cotton, Flavr savar tomato, Brassica napus, Golden rice etc

Transgenic plants are generated by introducing foreign DNA into a cell and regenerating a plant from the cell. This process is known as genetic transformation and involves the transfer of genes from one organism to another. The foreign DNA that is introduced into the plant cell is usually derived from a different species, allowing the plant to express new traits or characteristics.

Here is a detailed explanation of each option and why option C is the correct answer:

a) Produced by a somatic embryo in an artificial medium:
Somatic embryogenesis is a technique used to produce somatic embryos from plant cells. However, the term "transgenic plants" specifically refers to plants that have been genetically modified by the introduction of foreign DNA. While somatic embryogenesis can be used to produce transgenic plants, it is not the defining characteristic of transgenic plants.

b) Produced after protoplast fusion in an artificial medium:
Protoplast fusion is a technique used to combine the protoplasts (cells without cell walls) of two different plant species. This technique can be used to create new plant hybrids, but it does not necessarily involve the introduction of foreign DNA. Therefore, while transgenic plants can be produced through protoplast fusion, it is not the defining characteristic of transgenic plants.

c) Generated by introducing foreign DNA into a cell and regenerating a plant from the cell:
This option accurately describes the process of genetic transformation, which is the defining characteristic of transgenic plants. In this process, foreign DNA is introduced into the plant cell using various techniques such as Agrobacterium-mediated transformation or particle bombardment. The foreign DNA integrates into the plant genome, and the transformed cells are then regenerated into whole plants. These transgenic plants can express the traits encoded by the introduced foreign DNA.

d) Grown in an artificial medium after hybridization in the field:
Hybridization refers to the cross-breeding of two different plant varieties or species to create new hybrids. While hybridization can produce new plant varieties, it does not necessarily involve the introduction of foreign DNA. Therefore, while transgenic plants can be generated through hybridization, it is not the defining characteristic of transgenic plants.

In conclusion, transgenic plants are generated by introducing foreign DNA into a cell and regenerating a plant from the cell. This process allows the plant to express new traits or characteristics encoded by the introduced foreign DNA.