Question

the pony express
in the gold rush of 1849, some one hundred thousand immigrants were lured to
california by the promise of gold. towns and businesses popped up to accommodate the
growing population, but a problem remained: how to communicate across the vast
reaches of the united states. three businessmen thought they had an answer: faster
mail delivery via the pony express, a relay system of horses and riders. the pony express
made its first delivery on april 14, 1860. mail from st. joseph, missouri, reached san
francisco in just eleven days, rather than a month or more, which was standard for mail
delivery at the time. the pony express was a short-lived solution, however. after just
eighteen months, it was replaced by a national telegraph wire.
what is the main, or central, idea of the passage?
the pony express was a chain of horses and riders across the country used to
deliver mail.
the pony express allowed for faster communication in the rapidly growing
united states.
on april 14, 1860, the pony express delivered mail from missouri to california
in just eleven days.

Explanation:

The passage first sets up the communication problem in the growing U.S. after the 1849 Gold Rush, introduces the Pony Express as a faster mail delivery solution, notes its speed, and then mentions its short lifespan. The first option only describes what the Pony Express was, not the central point of the passage. The third option is just a specific detail about its first delivery. The second option captures the core purpose and context: the Pony Express solved the need for faster communication in the expanding U.S.

Answer:

The Pony Express allowed for faster communication in the rapidly growing United States.