Effective communication is obviously influenced by different fators among which we can surely include acceptance of responsibility. You have to consider that when someone is taking responsibility for his actions this will make the person who he's talking to view him more favourably, as a more responsible person and perhaps even as someone who wants to sensibely solve problems.
You would use a open stance.
The answer is B. chemicals.
the reason its b is because A= bacteria but u have to clean the bacteria in the water so its not A and its not c. becouse that will be just turning the ice into water .so the answer is b. becouse we use chemicals everyday to get rid of bacteria and waste