Natural selection is an evolutionary mechanism by which (B.) advantageous traits become more common in a population.
He discovered a new type of medicine that could treat infections.
He discovered the 1st antibiotic (penicillin).
Jet streams are fast moving air currents much like how a river is a fast moving water current so the answer is jet streams.
Since Australia is located in the Pacific ocean, extremes of weather and climate happen throughout a season. El Niño is traditionally defined as a dry climate with reduced rainfall; in this happens to be more extreme in Australia because of its location. La Niña on the other hand is traditionally defined as a wet or cool climate with lots of rainfall; and this is indifferent as La Niña in Australia tend to be more extreme too.
