Why did the Black Death never become "endemic" in Europe? * a, The climate caused the rats and fleas that carried the plague to die.
b The plague moved to China and India in 1855.
c vaccine was created for the Bubonic Plague.
d Everyone understood that good hygiene killed the bacteria.

D. everyone understood that good hygiene killed the bacteria

In addition to them learning this, they implemented strategies of quarantine, as they would isolate anyone who was effected by the plague. Isolating these people was the most effective strategy, as it would either die off or killing bacteria would rid healthy people of the plague.

The correct answer is: People wanted the bridge built because it would be good for business.

Explanation:

In the excerpt, the author clearly states that the people wanted to build a bridge because they considered it would be good for business. We can also conclude that from the following sentence: The irresistible demands of commerce enforced these hard conditions.

As we can notice, this irresistible need of commerce enforced the hard conditions for the construction of the bridge, and people doubted the construction would begin at the earnest.

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