The following is an excerpt from a draft of an essay about New York City's postal history.
In the late 1890s, New York City struggled to manage its rapidly growing volume of mail, as horse-drawn wagons routinely became gridlocked in congested streets. To resolve this crisis, the post office installed a network of underground pneumatic tubes that propelled mail canisters beneath the city streets at speeds of up to thirty miles per hour. At its peak, this subterranean network moved millions of letters daily across Manhattan and Brooklyn.
[1] ___________________________________________________________________. In 1918, the federal government suspended funding for the pneumatic system in order to prioritize the war effort. Following the war, the postal service chose to invest in automobile trucks, which could carry larger volumes over greater distances, and by 1953, the last of the city's pneumatic mail tubes were permanently shut down.
Which choice most effectively introduces the second paragraph by establishing its main focus?
- However, the subterranean system's era of dominance proved to be relatively short-lived.Answer
- BAlthough the pneumatic tube network was a technological marvel that drastically reduced mail delivery times in the city.
- CBecause the underground tubes eventually became too expensive to maintain; the postal service looked for other options.
- DFurthermore, the city's expanding geography is requiring new ways to transport mail.