The correct option is
B Ernst Haeckel
Embryological support for evolution was proposed by Ernst Haeckel. His theory was based upon the observation that certain features are common to all vertebrates during the embryonic stages. He proposed this concept as ‘biogenetic law’ or ‘recapitulation theory’ which states that “ontogeny (embryonic developmental history) recapitulates phylogeny (evolutionary history)”. This means that an organism repeats its ancestral history during the stages of its embryonic development. For example, the embryos of all vertebrates including humans develop a row of vestigial gill slits just behind the head but it is a functional organ only in fish and not in other adult vertebrates. This shows that all vertebrates originated from a common ancestor.
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Oparin and Haldane gave the theory for the origin of life called the chemical theory of evolution. They stated that ‘life’ originated on earth from the pre-existing non living organic molecules (e.g., RNA, protein, etc.) which were formed from inorganic constituents.
According to Charles Darwin, there has been a gradual evolution of life forms governed by natural selection. The individuals which were reproductively more fit were selected by nature and survived and left more progeny than the lesser fit life forms.
Stanley Miller supported Oparin and Haldane’s theory of the origin of life. He performed an experiment to simulate a reducing environment. A mixture of methane, ammonia, hydrogen and water vapour, exposed to high electric voltage and temperature led to the synthesis of amino acids.