Question

the primary reason that the human population has grown rapidly over the past 100 years is that there has been
a. ○ a decrease in cancer rates due to scientific research.

b. ○ more access to light and electricity.

c. ○ more access to renewable resources.

d. ○ an increase in food supplies and better access to clean water.

Explanation:

Rapid human population growth over the past century is primarily driven by factors that reduce mortality rates and support survival. An increase in food supplies (via agricultural advancements) and better access to clean water (reducing waterborne diseases) directly improve nutrition and health, lowering death rates and enabling more people to live longer, which fuels population growth. Other options are incorrect: A (decreased cancer rates from research is a minor factor), B (access to light/electricity is indirect), and C (renewable resources access is not a primary driver of historical population growth).

Answer:

D. an increase in food supplies and better access to clean water.