What factor does not contribute to "water stress" on the earth?

a) less ocean water sources
b) population differences
c) precipitation differences
d) economic resources

The term “water stress" describes the suffering in a region caused by the water scarcity (the lack of fresh water resources) in that area. Overconsumption, growing population , institutional or financial issues are also factor that contribute to water scarcity.  Precipitation differences is not one of them. Correct C

a. the production of carbon dioxide through the process of photosynthesis

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