To solve this problem, we need to identify who first provided unequivocal proof that DNA is the genetic material. Let's analyze the contributions of each option:$\newline \bullet$Frederic Griffith:$\newline$ - Griffith conducted experiments in 1928 demonstrating the phenomenon of transformation in bacteria.$\newline$ - However, he did not identify DNA as the genetic material.$\newline \bullet$Avery, MacLeod, and McCarty:$\newline$ - In 1944, they provided evidence that DNA is the transforming principle in bacteria.$\newline$ - Their work suggested DNA as the genetic material but was not considered unequivocal proof at the time.$\newline \bullet$Alfred Hershey and Martha Chase:$\newline$ - In 1952, they conducted experiments using bacteriophages and radioactive labeling to show that DNA, not protein, is the genetic material.$\newline$ - Their experiments provided unequivocal proof that DNA is the genetic material.$\newline \bullet$Wilkins and Franklin:$\newline$ - They contributed to the understanding of DNA structure through X-ray crystallography, but did not provide proof of DNA as the genetic material.$\newline$Therefore, the correct answer is Option 2: Alfred Hershey and Martha Chase.