Final answer:
Frederick Griffith was the first scientist to show that cells could undergo transformation through the transfer of genetic material, which he called the 'transforming principle'. Option 1 is correct.
Step-by-step explanation:
The scientist who first demonstrated that cells contain some component that can be transferred to a new population of cells and permanently cause changes in the new cells was British bacteriologist Frederick Griffith.
In 1928, Griffith conducted experiments with Streptococcus pneumoniae, showing that a transforming principle from heat-killed virulent strains could transform live non-virulent strains into virulent ones. Later on, Avery, MacLeod, and McCarty identified this transforming principle as DNA, setting the stage for further research into the molecular nature of inheritance.
Griffith's findings were groundbreaking, as they suggested a horizontal transfer of genetic material, meaning that hereditary information could be transferred between cells within the same generation. His experiments paved the way for future discoveries, such as those by Avery, MacLeod, and McCarty who, through molecular purification techniques, proved that DNA was responsible for this transformation.
Consequently, these studies by Avery and his team provided substantial evidence that DNA is the material of heredity, which was later confirmed by the experiments of Hershey and Chase.