Which of the following sentences is the correct passive form of this active sentence?If the police hadn’t arrived to stop the gangs, there would have been a riot.
A. If by the police the gangs hadn’t been stopped, there would have been a riot.
B. If the police hadn’t stopped the gangs, there would have been a riot.
C. If the gangs hadn’t by the police been stopped, there would have been a riot.
D. If the gangs hadn’t been stopped, there would have been a riot.