urvi470 Here's a rundown of how the different forms work in this case
Facilitated: In all the choices where it appears, "facilitated" serves as a verb describing what the brokerage house did. (Sometimes past participles (-ed forms) can serve as noun modifiers, but that doesn't happen here.)
Facilitating (no comma): In A, "facilitating" serves as one part of an adverbial modifier (parallel with "delivering"). In this case, the modifier doesn't fit properly into the
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Facilitated: In all the choices where it appears, "facilitated" serves as a verb describing what the brokerage house did. (Sometimes past participles (-ed forms) can serve as noun modifiers, but that doesn't happen here.)
Facilitating (no comma): In A, "facilitating" serves as one part of an adverbial modifier (parallel with "delivering"). In this case, the modifier doesn't fit properly into the
...
