Donizetti's Gemma di Vergy, as well as many other bel canto operas of the first half of the 19th century, is infrequently produced today, mostly on account of requiring singers with a virtuosic vocal ability in all of the roles.
A. on account of requiring singersB. on account of their requiring a singerC. because it requires singersD. because of it requiring singersE. being that it requires a singer

Explanation:

Donizetti's Gemma di Vergy, as well as many other belcanto operas of the first half of the 19th century, is infrequently produced today, mostly on account of requiring singers with a virtuosic vocal ability in all of the roles.

A.on account of requiring singers

B.on account of their requiring a singer

C.because it requires singers

D.because of it requiring singers

E.being that it requires a singer

The use of "on account of" with a gerund ("requiring") is wordy and unidiomatic.Option C conveys the meaning in the simplest form and hence is the correct option. All other options are awkwardly wordy.

the answer is b just took the tested