A scientific paradigm is a framework which contains all of the distinct, established patterns, theories, common methods and standards that allow us to recognize an experimental result as belonging to a field or not.
Both options A and C fit as scientific frameworks for the building of various theories and conducting experiments.
Neo Darwinism is generally used to describe any integration of Darwin's theory of evolution by natural selection with Gregor Mendel's theory of genetics. This paradigm provided a robust framework from which several theories and theory-revisions of evolution were made.
The Copernican model of the solar system is a paradigm that describes the planetary revolutions of the solar system following the heliocentric model, with the Sun at the center of the Solar System.The reasoning pattern, served as framework for the development of other theories. like Kepler's laws, Theory of relativity, etc
The other options B and C are just theories or hypotheses drawn out from other paradigms they do not provide the robust framework for scientific discovery that a paradigm does.
"The best description how the common cold spreads in the human body is by the replication of virus inside the respiratory track (cells of respiratory tract) of the body."
