In 1953 S. L. Miller created primitive earth conditions in the laboratory and gave experimental evidence for origin of first form of life from preexisting non-living organic molecules. The primitive earth conditions created include

(a) low temperature, volcanic storms, atmosphere rich in oxygen

(b) low temperature, volcanic storms, reducing atmosphere

(c) high temperature, volcanic storms, non-reducing atmosphere

(d) high temperature, volcanic storms, reducing atmosphere containing CH₄, NH₃ etc.