In nature, selective pressures on populations are varied and interrelated. Select the primary type of selection best describing the situations below based on the information presented. Pathogenic bacteria found in many hospitals are antibiotic resistant. Brightly colored peacocks mate more frequently than do drab peacocks. Fossil evidence indicates that horses have gradually increased in size over geological time. The cheetah is reputed to be the fastest land mammal. The evolutionary process that gave rise to this speed is most likely what kind of selection? A certain species of land snail exists as either a cream color or a solid brown color. Intermediate individuals are relatively rare.

Pathogenic bacteria found in many hospitals are antibiotic resistant.

Explanation:

Antibiotics are drugs that have the ability to kill pathogenic bacteria, especially in hospital environments, where infection cases are more frequent and can be very serious.

However, in a population of pathogenic bacteria, there may be some that, somehow, are resistant to antibiotics. Thus, while the entire population of bacteria dies with the presence of antibiotics, they survive, reproduce and give rise to another population of bacteria that are not affected by the antibiotic. In this case, there was an evolution generated by natural selection, allowing pathogenic bacteria found in many hospitals to be resistant to antibiotics.

image result for describe the various types of gene mutationsghr.nlm.nih.gov

the types of mutations include: missense mutation: this type of mutation is a change in one dna base pair that results in the substitution of one amino acid for another in the protein made by a gene. nonsense mutation: a nonsense mutation is also a change in one dna base pair.

explanation:

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.