If resources become scarce, which effect is most likely on a population?

• A. The population will instantly shrink to zero.
• B. The population growth slows until it reaches carrying capacity.
• C. The birth rate will triple.
• D. There will be no effect.

Answer: (B)

Resource scarcity acts as a limiting factor that slows population growth. When food, water, and other necessities become limited, individuals compete more, survival of offspring drops, and the birth rate doesn’t stay high while the death rate may rise. As a result, the population grows more slowly and eventually levels off at the environment’s carrying capacity—the maximum number the environment can support long-term with the available resources. This explains why growth slows and stabilizes rather than shrinking instantly or increasing without limit. The other options don’t fit because scarcity doesn’t cause immediate extinction, a sudden tripling of births, or no effect at all.