Why Did the Researchers Wear Protective Clothing and Note So

Multiple Choice

Why did the researchers wear protective clothing and note so emphatically that they did so?

A) They needed to be certain there were no ancient pathogens on the sample that modern humans hadn't been exposed to.
B) They needed to be sure not to harm the precious sample with oils from skin or moisture from their breath.
C) They needed to minimize the chance of introducing their own mitochondrial DNA to the sample.
D) Because the work was done in Germany,they needed to follow stringent,standard German laboratory procedures and document their compliance.