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In 1928, Frederick Griffith published his work with two strains of Streptococcus pneumoniae and their abilities to infect and kill mice. He noted differences between an encapsulated S strain that appeared smooth when grown on agar plates and a non-encapsulated R strain that appeared rough by comparison when grown on agar plates. Using various combinations of living and heat-killed R and S strains, he demonstrated the process of transformation and proposed the existence of a transforming principle.

Based upon his experimental design, which strain or combination of strains of Streptococcus pneumoniae resulted in the killing of mice, demonstrating transformation?


Dead capsulated (S) strain alone.


Dead capsulated (S) strain + dead non-capsulated (R) strain.


Live non-capsulated (R) strain alone.


Dead capsulated (S) strain + live non-capsulated (R) strain.


Dead non-capsulated (R) strain alone.

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