What radical move was carried out by the national assembly on august 4th?

It is the abolition of the Feudal System that in French society since Medieval Period. The old feudal system left France in ruins and in verge of collapse and the changing times needs new reforms and replacement of the old rules and regulations that are left unchanged for centuries. Such actions change the system of taxation and many more to a more fair and justifiable standard and more effective at the time it takes place.

C.? (I think)

Explanation: