Answer:
d. has acquired naked DNA from the environment
Explanation:
Bacterial transformation is a process whereby a living bacterium takes up pieces of DNA from the environment and the foreign DNA becomes incorporated into the genome of the bacterium thereby 'transforming' it genetically.
A transformed bacterium does not necessarily die within 48 hours, all other factors being considered.
Transformation does not hinder a bacterium from forming conjugation pilus.
Transformation does not always make a bacterium to be lethal to mouse. It depends on the gene present in the foreign DNA.
The correct option is d.
