Final answer:
An episome is a type of plasmid capable of existing independently or integrating into a bacterial chromosome, playing roles in processes such as antibiotic resistance and genetic engineering in research.
Step-by-step explanation:
An episome is b. a plasmid that may exist separately or be integrated into the main chromosome. Plasmids contain genes that can be beneficial to the bacterial host, like resistance to antibiotics or the ability to produce antibiotics. In the context of prokaryotic genetics, transduction is a process where bacteriophages, which can infect bacteria, introduce foreign DNA into bacterial cells. There are two types of transduction: generalized and specialized. In generalized transduction, any piece of chromosomal DNA may be transferred, while specialized transduction involves the imprecise excision of a lysogenic prophage that carries with it specific chromosomal DNA. Furthermore, an episome can be part of engineered phagemids used to introduce recombinant DNA into host cells for research purposes.