A normal range in adults is generally considered to be 4.35 to 5.65 million red blood cells per microliter (mcL) of blood for men and 3.92 to 5.13 million red blood cells per mcL of blood for women. In children, the threshold for high red blood cell count varies with age and sex.
I would say the answer is A. moistens and filters incoming air.
Answer:
The answer to the question is Habitat
A strain is a low-level taxonomic rank used at the
intraspecific level (within a species). While the majority of the members of the same species have very high similarity in their genomes, there occasionally is a proportion of the species that has a little different genome from the popular species group. This variability results in different strains on the species.
A harmless Staphylococcus
aureus may have a muted virulence gene. However, either due to mutation of the
gene or recombination with the harmful strain, a harmless Staphylococcus
aureus could easily turn virulent (harmful).