Bacteria are usually identified by using standard molecular biology procedures, being the Polymerase Chain Reaction (PCR) the most widely used technique for this purpose. The identification by PCR consists of the amplification and visualization of specific DNA sequences that can be obtained from different individuals, strains, species, etc. However, it is also possible to identify bacteria with a microscope, i.e., by observing taxonomical characteristics that allow to differentiate specific bacteria.
It would be B) unconscious. I know this because when you're not thinking about something it is not in your conscious mind, so it would be in your unconscious mind.