Answer:
Population and resources
Step-by-step explanation:
By defining the term carrying capacity of earth, we can think of it as " the maximum number of people whose survival can be supported by earth".
Studies have predicted that the carrying capacity of earth can be somewhere between 2 billion to 40 billion individuals. But it can not be calculated in specific number because it depends on the availability of resources.
With the increase in development and progress in modes of communication, travel, food etc, all these advancements have put alot of burden on mother nature where the resources are declining at a rapid pace. The fossil fuels being limited resources can be consumed earlier than our prediction due to increase in population and the search of human towards an easier lifestyle. This is putting alot of pressure on earth to maintain the carrying capacity at a higher rate. Therefore, carrying capacity is determined by the number of people our earth can support or population as well as resources earth has to offer.
Hope it helps!