As a force for adaptation, natural selection acts upon the:

your answer is "the 1950's"

answer; i believe the answer is (polygenic inheritance;

well, i believe that the answer is 2. : 3

one part of the electromagnetic spectrum that arrives on earth as solar radiation from the sun is the visible spectrum. wavelengths of the visible spectrum combine to form what we refer to as

answer - d) ultraviolet radiation.

violet /   380–450 nm / 668–789 thz

violet is number 1 in the chart of visible light.