Final answer:
The Avery, MacLeod, and McCarty experiment showed that when DNA was degraded, it lost its ability to transform bacteria, supporting the conclusion that DNA was the transforming principle.
Step-by-step explanation:
The Avery, MacLeod, and McCarty experiment provided evidence that DNA was the transforming principle. They conducted a series of experiments in which they isolated various components of the S strain bacteria, such as proteins and nucleic acids (RNA and DNA), and tested their transforming ability on the R strain bacteria. They found that when DNA was degraded, the resulting mixture was no longer able to transform the bacteria, while all the other components could.