שאלה | When analyzing drinking water for potential contamination, you should:

When analyzing drinking water for potential contamination, you should:

		test for fecal coliforms and Escherichia coli but make the decision regarding whether the water is safe or unsafe based on the E. coli.
		test for E. coli and, if detected, decide whether the water is safe or unsafe based on the E. coli origin (human, livestock, or wild animals).
		test for total coliforms, as drinking water should contain none.
		test for E. coli and, if detected, further test to establish whether it is pathogenic