The correct option is Improvements in sanitation and health conditions..
Explanation
The Demographic Transition Theory describes the transition of a society from high birth and high death rates to low birth and low death rates as it progresses from an agrarian to an industrial and urbanized society. This transition typically occurs in distinct stages, influencing the overall population growth rate.
Option Analysis
- Implementation of strict population control laws. is incorrect: Implementation of strict population control laws is generally aimed at reducing birth rates (fertility), which is a characteristic feature of the Third Stage or late transition, not the primary cause of mortality decline in the Second Stage.
- Improvements in sanitation and health conditions. is correct: The Second Stage of the demographic transition is characterized by a significant decline in mortality (death rates) while fertility (birth rates) remains high. This decline in mortality is primarily driven by improvements in sanitation, medical facilities, and public health, alongside better food security. These factors drastically reduce the incidence of epidemics and disease-related deaths.
- Large-scale migration to urban areas. is incorrect: While migration to urban areas (urbanization) often accompanies the demographic transition, it is not the fundamental biological or infrastructural cause for the reduction in mortality rates.
- Significant increase in agricultural exports. is incorrect: An increase in agricultural exports does not directly correlate with a decline in domestic mortality. While improved agricultural productivity (food security) is relevant, the specific act of exporting is not the determinant factor.
Key Takeaway
Stage II (Population Explosion) is defined by a sharp drop in the Death Rate due to medical and sanitary improvements, while the Birth Rate remains high, leading to a high rate of natural increase.