Q: Competent bacteria cells are capable of taking up plasmids. A scientist in a lab intends to amplify a specific plasmid by transforming a competent strain of bacteria with the plasmid in question and then letting the bacteria divide. The scientist can then isolate the bacterial genetic material, which includes now includes the plasmid. The plasmid also encodes a gene for ampicillin resistance (which is not encoded in the competent bacteria cells), allowing transformed bacteria to grow on agar plates containing ampicillin. A negative control is used to determine if a confounding variable is affecting an experiment's results. Negative controls are groups in which we would not expect a result when applying all of the experiment`s conditions except for the independent variable. Which of the following can act as a negative control to ensure that the bacteria that grow on the agar containing ampicillin are transformed bacteria?
A		Just distilled water
B		Just competent bacteria cells
C		Just plasmid
D		Just bacterial cells and plasmid

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