How to disinfect drinking water in the wilderness<br>Pack the proper water purifying equipment and chemicals. If you're backpacking you should have a high quality pump with a filter, and/or purifying tablets. Immerse the end of the pump where water flows in in the clearest portion of the water source that you can see.

Choose your answer: based on the paragraph above can we conclude that "the water has to be flowing"?

OPT:
(i) Yes
(ii) It's impossible to say
(iii) No
I think the answer is
(ii)