שאלה | Why might routine monitoring of drinking water miss detecting microorganisms in biofilm form?

Why might routine monitoring of drinking water miss detecting microorganisms in biofilm form?

		Because it is difficult to culture microorganisms in biofilm form
		Because cells confined within the biofilm are not free living and, thus, may not be found in the water sample.
		Because routine monitoring of drinking water is done only for fecal-related bacteria, which cannot form biofilms.
		Because routine monitoring of drinking water is done only for aerobic bacteria, which are free living and do not form biofilm.