Explanation:

Correct Answer is (d).According to the given context, it is regarding the ideas of colonialist middle class and the sentence is about the very common notion of such classes under the colonial regime.
Now, coming to the options, Only D can be used since both the words can imply meaningful connotations in the given context and the statement will also be correct. Other options are not correct since either both the words or one of them will not fit in the respective blank. Therefore, they can be eliminated.
The correct sentence would be:
Clearly, anyone familiar with social transition under colonialism would know, that such notions of the colonial middle class were those defined by the colonialist.
This makes option D the correct choice among the given options.