Helmut Haberl and colleagues have compiled data on as a measure of how human population growth impacts Earth's natural resources and ecosystem services.

Consumption of net primary productivity

Explanation:

The net primary productivity can be defined as the gross primary productivity subtracting the rate of energy loss for maintenance and metabolism.

The products that is being produced by the producers are used by the people is known as biomass.

Helmut Haberl along with its colleagues have compiled the data on the usage of the primary productivity and its effect on the resources available by the nature to the mankind.

just finished the test, the answer is d, greg is the least cost-effective because he charges the most for the project