Answer:
B. Resource availability sets the limit.
Explanation:
The more resources available, the higher the carrying capacity, the less resources available, the lower the carrying capacity.
For example, take a grassland. Let's say that the grassland can support 100 deers. if there was a sudden drought, causing most of the grass to die, the carrying capacity can drop down to 10. If there was suddenly constant adequate rainfall, and silt was deposited in the land, causing more grass to grow, the carrying capacity can grow to upwards of 125.
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