What was the experimental variable that Avery used when he repeated Griffith's work?

the type of molecule-destroying enzyme he used

Explanation:

Frederick Griffith and Oswald Avery were scientific researchers who discovered DNA. Frederick Griffith began the research and Oswald Avery continued his research in 1944 when they made the discovery of DNA. When Avery repeated Griffith's research the experimental variable in Avery's experiment was the type of molecule-destroying enzyme he used.