Which of the Following Is Not a Potential Application of Biofilms

Multiple Choice

Which of the following is not a potential application of biofilms?

A) The creation of an impermeable film to protect teeth from decay.
B) A biofilm "transplant," composed of beneficial gut microbes to replace microbes known to cause obesity.
C) The use of biofilm formation as a qualitative indicator of cell density.
D) The introduction of biofilms to break down metal waste.
E) The study of fossilized biofilms to evaluate and learn about the history of life on Earth.