Question

2 multiple choice 5 points why were early public health efforts focused on ports and large cities? to ensure more efficient communication and governance due to higher population densities leading to rapid disease spread arrival of passengers and crews on ships bringing infectious diseases, such as cholera and yellow fever to promote trade and commerce by improving infrastructure

Explanation:

Early public - health efforts focused on ports and large cities mainly because ports were entry - points for infectious diseases carried by passengers and crews on ships (such as cholera and yellow fever), and large cities had high population densities which facilitated rapid disease spread.

Answer:

due to higher population densities leading to rapid disease spread, arrival of passengers and crews on ships bringing infectious diseases, such as cholera and yellow fever