While on an Archaeological Dig in Europe, You Find a Stone

While on an archaeological dig in Europe, you find a stone tool that is rounded on one side and has had flakes removed from the other side, giving it the appearance of a tortoise shell. This is likely to be:

A) a prepared core typical of prehistoric modern humans that inhabited this region.
B) an example of the Levallois technique of Homo erectus.
C) a completed tool that is similar to those you have seen from the Solutrean toolkit.
D) none of the above