The correct option is
D breaks
Throughout the poem, the poet criticises the wind for crumbling things and destroying the weak. Let's find a synonym for 'crumbling'.
Option A - The wind not only throws, it also crushes, breaks and destroys everything. Since the criticism is about 'crumbling', we can't say it throws. Hence, option A is incorrect.
Option B - The wind damages a lot of things, but the criticism is for the crumbling of the weak things and people. Hence, option B is incorrect.
Option C - The wind crushes everything according to the poet, but it's not the synonym of 'crumbling'. Hence, option C is incorrect.
Option A - 'Crumbling' also means to break or disintegrate. Hence, option A is the correct answer.