Human activity leading to the emission of greenhouse gases may be a cause of global warming.
According to the precautionary principle, what should be done about greenhouse gas emission?
A. Analyse historical records from monitoring stations to see the trends in carbon dioxide emissions
B. Obtain more evidence by carrying out research on greenhouse gas emission
C. Take measures to lower greenhouse gas emission without further evidence
D. Develop strategies for coping with higher global temperatures

C

Some teachers found this question confusing and it is true that the precautionary principle is not the easiest. The teacher’s notes indicate that in this context the precautionary principle dictates that if the effects of a human-induced change would be very large, those responsible for the change must prove that it will not do harm before proceeding. In this question proceeding would be continuing to emit greenhouse gases. Answer B implies that emissions should continue until there is evidence of harm, so it does not follow the precautionary principle. The expected answer is C, which states that measures should be taken to reduce emissions before waiting for further evidence of harm to be produced.