EXAMPLE : The Victoria and Albert Museum ...

Although it was once funded entirely by the government, the Victoria and Albert Museum was one of the first of Britain’s national museums seeking support from corporations and private donors and to increase income by increasing attendance. 

(C) among Britain’s first national museums to seek support of 
(D) among the first of Britain’s national museums to seek support from 

C says that there are many "first national museums ( to seek ...)" and Victoria is one of them. But the intended meaning is unclear.

It should be D.

Notes

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