Final answer:
Acheulean tools are known as teardrop-shaped hand axes made by careful chipping of stone cores to create a symmetrical and sharper artifact, representing a key development in human toolmaking technology.
Step-by-step explanation:
When examining stone tools and their corresponding technological industries, it is important to recognize the defining characteristics associated with each. Acheulean tools are recognized as teardrop-shaped hand-axes and were part of a more sophisticated stone tool industry that represented a significant advancement over the previous Oldowan tools, which were more primitive and crude. Acheulean hand-axes exhibit carefully chipping away of flakes from a stone core, creating a symmetrical biface with a sharper and more uniform cutting edge. This technique contrasts with the former Oldowan industry, where tools were less refined and made primarily from chipped cores.
The development of Mousterian tools, which are characterized by smaller hand axes and tools made from stone flakes rather than cores, marked a progression in toolmaking techniques. This advancement allowed flakes, rather than just the cores from which they came, to be used as implements themselves. Meanwhile, the Upper Paleolithic era signaled a further evolution in toolmaking, with the introduction of blade tools and the use of materials such as bone and antler for creating a more diverse set of tools. Of the options provided, Acheulean tools best fit the phrase 'hand-axes made by careful chipping of stones.'