579 - Logical Reasoning

Russia's aggressive fishing in the prime fishing grounds of the Northern Pacific has led to a sharp decline in the populations of many fish and a general increase in the retail price of fish. This same pattern has occurred with far too many of our scarce vital natural resources, resulting in high prices for many products. It is likely then, that fish prices will continue to rise in the near future.
In making the argument above, the author relies on all of the following assumptions EXCEPT:

1. The scarcity of fish is a determining factor in its price.
2. The decline in the number of fish available will result in higher prices for fish in stores.
3. There will not be any substantial decrease in other costs involved in the fishing process that could keep the price of fish from increasing.
4. Fish populations will not recover in the near future.
5. Fishing practices can substantially influence the demand for fish.