A. the authorities
in New York disabled most of the control buttons
that had once operated pedestrian-crossing lights in the city after they observed
Will come back to this choice later.
B. the authorities
in New York had disabled most of the control buttons
that once operated pedestrian-crossing lights in the city after observing
had is wrong
C. most of the control buttons
that once operated lights at pedestrian-crossing in the city were disabled
after the authorities
in New York had observed
after-had doesn't make sense.
a) After observing -- okay
b) after had observed -- wrong.
D. the authorities in New York disabled most of the control buttons
that once operated pedestrian-crossing lights in the city after observing
Will come back to this choice later.
E. most of the control buttons
operating pedestrian-crossing lights in the city are
being disabled since the New York authorities observed
wrong usage of being
Between A and D
A is wrong becuase meaning wise its wrong. It states that authorities disabled most of the controls that had once operated. If the buttons already stopped working, what was the need to disable them? Lol
Split 1: 'the authorities' vs 'most of the control buttons'- subject after the modifier
If we go with 'the authorities', we end up with a sentence that is active over sentences in option C & E- which are passive.
Split 2: 'Had once operated' vs 'once operated'
We don't need the past perfect tense here since the government did not disable buttons that were already out of use. Simple past is the right tense because the events were happening simultaneously. Option A and B are out.
Option D is the best one.