Answer:
c. The harmless bacteria had been transformed.
Explanation:
Fredrick Griffith carried out the first experiment that showed bacteria can get DNA by transformation in 1928.
He used two different strains of the bacteria Streptococcus pneumoniae a)type-III-S or smooth strain-Covered by a protective polysaccharide capsule hence lethal
b) type II-R or rough strain-Lacked the polysaccharide hence non-lethal
In his experiment he observed heat killed Type-III-S strain was not able to kill the mice. However, when its remains was added with rough strain then the blend was able to kill the mice.
When he collected blood from the dead mice it had live strains of both smooth and rough type.
He came to a conclusion that non-lethal type II-R strain was transformed into lethal type II-S strain by a "transforming principle" that was supposed to be the part of dead III-S strain bacteria.
