Final answer:
The gene coding for host cell attachment is likely to be found in a genomic island of a pathogenic bacterial strain and not in a non-pathogenic strain, as it confers the ability to adhere to and invade host tissues.
Step-by-step explanation:
A gene coding for proteins that is likely to be found in a genomic island of a pathogenic bacterial strain and not found in a non-pathogenic strain is typically associated with virulence or antibiotic resistance factors. Such genes could enable bacteria to attach to host cells, produce disease-causing toxins, or withstand antimicrobial agents. In this context, the correct answer is d. host cell attachment, as genomic islands often carry genes that help a pathogen adhere to and invade host tissues, a characteristic not generally found in non-pathogenic strains.
Genes for antibiotic resistance can be transferred among bacteria through various mechanisms, such as conjugation, transformation, or transduction, and these events can occur between non-pathogenic and pathogenic bacterial strains. When antibiotic resistance genes are acquired by pathogenic bacteria, they can become more difficult to treat, leading to the potential development of so-called "superbugs."
RNA polymerase, tRNA aminoacyl synthase, and glucose transporters are more fundamental to cell function and would be present in both pathogenic and non-pathogenic bacteria. Therefore, these options do not specifically relate to traits that distinguish pathogenic bacteria in the context of genomic islands.