What distinguishes a transgenic organism from other organisms?

A transgenic organism is specifically characterized by the incorporation of foreign DNA into its genome. This genetic modification allows the organism to express traits from another species, which may not naturally occur in its own genetic makeup. For instance, scientists might introduce a gene that allows a plant to be resistant to pests or a gene that enables better stress tolerance in animals. This process is distinct from simply breeding organisms or other forms of genetic variation that do not involve the direct introduction of foreign genes.

The other choices do not accurately capture the primary characteristic of transgenic organisms. While some transgenic organisms may exhibit faster growth or improved resistance to diseases, these outcomes are not defining features of transgenesis itself, and these traits can also be achieved in non-transgenic organisms through conventional breeding. Additionally, reproduction method does not determine whether an organism is transgenic; both sexually and asexually reproducing organisms can be genetically modified. Therefore, the critical factor that sets transgenic organisms apart is their genetic alteration through the insertion of foreign DNA.