Population growth is said to be explosive when growth rate is
**Core Concept**
Population growth rate can be described using the logistic growth model, which takes into account the carrying capacity of the environment. The growth rate is initially exponential, but as the population approaches its carrying capacity, it slows down due to resource limitations and other factors.
**Why the Correct Answer is Right**
Explosive population growth is characterized by a growth rate above 2% per annum, which is roughly the replacement rate. This rapid growth is often seen in areas with abundant resources, lack of effective family planning, and limited access to education. The key factor is the population's ability to outpace its carrying capacity, leading to rapid increases in population size.
**Why Each Wrong Option is Incorrect**
**Option A:** 0% growth rate is actually a state of zero population growth, where the birth rate equals the death rate, resulting in a stable population size.
**Option B:** A growth rate of 1% is considered low, and populations with such growth rates often experience gradual declines in fertility rates and aging populations.
**Option C:** A growth rate of 3% is still relatively high but not explosive. It may be seen in areas with rapid economic growth and improvements in healthcare, but the population growth is not yet outpacing its carrying capacity.
**Clinical Pearl / High-Yield Fact**
The concept of explosive population growth is crucial in public health, as it can lead to increased pressure on resources, environmental degradation, and decreased quality of life. Understanding the factors that contribute to explosive growth can help policymakers develop effective strategies for population management and resource allocation.
**Correct Answer:** D.