Question 50: Choose the correct answer in each sentence. Sefu Asamoah is an innovative architect who is ______ the traditional approach to improving space-efficient apartment buildings.

The answer is NO

Before the blank is 1 tobe, so it can’t be an infinitive (choice A) or a verb conjugated in the present simple for a third person singular subject (choice D). Because there is an object after the blank, it is necessary to fill in the Ving form, expressing the initiative of the action.

Sefu Asamoah is an innovative architect who challenges traditional approaches to the construction of space-saving apartment buildings.