The over-prescription of antibiotics since the 1940s has promoted the evolution of antibiotic resistant strains of many bacterial infections. this process can best be described as what kind of evolutionary force? (genetic bottleneck, genetic drift, founder's effect, natural selection, directional pressure.)

Antibiotics are the medicines which prevent and treat the bacterial infections by inhibiting their growth. Antibiotic resistance is the potential of a bacterium to withstand the effects of an antibiotic. It is a consequence of evolution through the process of natural selection. It occurs through the genetic mutation and the bacteria evolve through natural selection. The widespread use of the antibiotics has made many bacteria resistant through the process of evolutionary pressure driving natural selection. The bacteria carrying the genetic mutation of antibiotic resistance survive and reproduce passing the trait to their offspring.  

answer:

the water molecules are transferred from the roots to the stem or top parts of the tall tree because of important properties of water which are adhesion, cohesion and capillary action. cohesion is the property of water molecules keeps water molecules in a combined state by sharing of bonds between them at the atomic level. adhesion allows the interaction of water molecules with other substances or substrate. adhesion will cause the attachment of water molecules to the wall of the vessel (xylem) of the plant. capillary action occurs when the adhesive force to the vessel wall is stronger than the cohesive force between water molecules. capillary action mimics the transfer of water from a tube or pipe. in this way water utilizes its property to transfer water from down to top level of the plant.