The disk diffusion test is used to compare the effectiveness of antibiotics. The incubated plate (results) will show bacteria growth except where antibiotic has effects. The more effective the drug, the inhibition zone will be greater. So the most effective antibiotic is the one that has the largest inhibition zone around the test site.
Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product. These products are often proteins.
I'm assuming that the choices are the ways urban landfills use to increase decay rate for most trash? If so, then the answer would be '<span>increase the number of aerobic bacteria'. Increasing the number of aerobic bacteria increase the decay rate for most trash.</span>