What shows overfishing? 1. use of trawling 2. an increase in the median size of fish in a given population 3. an increase in the abundance of fish species in lower trophic levels 4. decreasing catch with increasing effort

4.

Explanation:

Overfishing occurs when there is a decrease in species of fishes because these species can not replenish in time due to excessive fishing.

So when this occurs more effort will need to be applied,but there will also be a decrease in catch