Answer:
C)gold and copper because they were soft enough to be hammered
Step-by-step explanation:
During the neolithic age humans still didn´t have enough technology or knowledge to forge metals, so the only metals that they could work with were the ones that didn´t requiere to be heated up in order to be moldable, copper and gold were the metals that were strong enough to be used in every day tools and still were moldable with just hammers and rocks.