What was a significant technological breakthrough that occurred during the paleolithic era?

One can say that dominating fire was one major breakthrough. Men were already using rock tools in this age and it was an amazing breakthrough in history of man, but learning how to dominate fire was a game changer. It made them live longer, since they had a way to scare the predators, make light at night and to defrost meat.

the world may never know

option d is correct. corroborated sources of historical evidence   is necessary to validate a claim about an event in history.

historians tend to use written sources, but audio and visual materials as well as artifacts are important objects that supply information to modern historians.

historical sources are usually divided into two categories: primary and secondary sources. depending on the historian's intent, some sources shift their designation. determining what type of sources toimplement, and the level of credibility and reliability of those sources, is a significant step in critical thinking for the historian.

explanation: