Today, the steel beams and girders of the city's skyscrapers are bolted together with special steel bolts and welded together. Compared with riveting, these connections are stronger, more quickly made, and require fewer men to accomplish.

Which choice is the best paraphrase of the text?

a
Steel beams and girders in today’s skyscrapers are constructed with specially made steel bolts. Then, they are welded together. These modern-day connections are put together more quickly and by fewer workers than the ones made in the past by riveting. They are also stronger.
b
Steel beams and girders in modern-day city skyscrapers have stronger connections and are put together more quickly and with fewer workers than connections formed by riveting.
c
Today, the steel beams and girders of the city's skyscrapers are bolted together with special steel bolts and welded together. Compared with riveting, these connections are stronger, more quickly made, and require fewer men to accomplish.
d
Today’s skyscrapers are built using steel bolts that are specially made for skyscraper construction. These bolts are welded together and create stronger connections than those made by riveting.