The graph shows the findings of a study commissioned by a group of marine policy makers. what should these people do to determine the economic impact of a reduced crab fishery in the area?
they should extend the years of the projection further.
they should measure the actual amount of acidification.
they should study the overall yield over time.
they should calculate the cost of the water cleanup.

Option C, They should study the overall yield over time.

Explanation:

The reduction in the production of carb  will adversely impact the economy. The effect on economy in monetary terms can be determined by evaluation the total reduction in the yield year on year.

This estimate will further help us to understand the negative impact of low carb production on other economic activities such as employment of fisherman, market seller, cold storage etc,

Thus, option C is correct.