Read the texr below in order to answer question.
On London’s Streets, Black Cabs and Uber Fight for a Future
Katrin Bennhold
Katrin Bennhold
LONDON — Shortly before 6 a.m., Zahra Bakkali tiptoed out of her bedroom for morning prayers. She prepared breakfast (black tea and toast with olive oil), saw her children off to school, then rode the elevator to the garage below her southeast London housing project. She unlocked her white Toyota Prius, switched on the Uber app and awaited the day’s first job.
In a modest bungalow on the opposite side of the city, Paul Walsh had coffee and toast with butter. He studied the sports pages (his soccer team, Queens Park Rangers, had been struggling) and waved goodbye to his wife and son. Then he fired up his black cab, which is actually half-pink with an Elvis ad from the Memphis tourism board, and set off for Heathrow Airport.
They travel the same streets every day, strangers but also adversaries in what has become a familiar 21st-century conflict: the sharp-elbowed ride-hailing company Uber, versus entrenched taxi companies.
And yet the clash in London is different, less about the disruptive power of an app, or a new business model, than about the disruption of Britain. London’s cabby wars echo the culture wars that fueled Britain’s vote last summer to leave the European Union — and that have brutally flared up again in recent weeks: immigrant versus native, old versus new, global versus national.
London’s black cabs trace their lineage to 1634. To earn a badge, cabbies spend years memorizing some 25,000 streets and 100,000 landmarks for “the Knowledge,” the world’s toughest taxi exam. Most cabbies are white and British.
Uber arrived in 2012, just before the London Olympics, but its 40,000 drivers already far outnumber the city’s 21,000 traditional cabbies. They use satellite navigation to find their way around. Most of them are nonwhite, and many, like Mrs. Bakkali, are immigrants.
Uber fares are about 30 percent lower than those of black cabs — a discrepancy that cabbies say signals a deliberate attempt to kill off their trade. “London without black cabs,” Mr. Walsh said, “would be like London without Big Ben.”
Source: https://www.nytimes.com/2017/07/04/world/europe/london-uk-brexit-uber-taxi.html?rref=collection%2Fsectioncollection%2Ftechnology
Read the extract below:
“Uber arrived in 2012, just before the London Olympics, but its 40,000 drivers already far outnumber the city’s 21,000 traditional cabbies. They use satellite navigation to find their way around.”
The highlighted relative pronoun “they” on the text refers to