Which of the following explains the significance of the qin dynasty introducing iron technology? 1) there was no more use of wood in the construction of public works 2) the army no longer had to use lead in the construction of their armor 3) soldiers now had stronger weapons than their previous bronze ones 4) the population increased as there were more cities built along the primary rivers

The correct answer is "3".

The Qin dynasty was the first dynasty of Imperial China which lasted from 221 BC to 207 BC. The Qin contributed to structure political power, achieving the unity of the country. They also greatly improved the military. Swords which were previously made of Bronze were know made if iron, greatly improving this weapons properties and maneuverability. The introduction of iron also led to the improvement of other weapons such as crossbows.

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