Which of the Following Is a Method Used to Insert

Multiple Choice

Which of the following is a method used to insert or transform cells with a plasmid?

A) add the DNA to bacterial cells that have been lightly treated with lysozyme to produce "holes" in the cell wall
B) add the DNA to a heated suspension of cells at 42°C
C) treat the bacteria with Ca²⁺,add the DNA,and briefly heat to 42°C
D) incubate the DNA with the cells overnight at 4°C