Answer:
A: Discovery of DNA as the genetic material
Step-by-step explanation:
DNA is the genetic material and stretch of DNA that codes for a specific protein is called as gene. Discovery of DNA as genetic material provided the physical proof of Mendel's factors that were responsible for transmission of genetic traits in his experiment.
Discovery of DNA as genetic material also established that genetic variations among individuals of the species as described by Darwin are due to minor differences in their DNA molecules.
Hence, discovery of DNA as genetic material led to acceptance of both Mendel's law and Darwin's theory.