Final answer:
The Ridgway, Pennsylvania wood-carving competition in February uses chainsaws for carving intricate sculptures out of wood logs.
Step-by-step explanation:
Ridgway, Pennsylvania, is home each February to a renowned wood-carving competition that features artists who use chainsaws as their primary tool. This competitive event showcases the skills of chainsaw artists as they transform logs into intricate sculptures. Unlike the crafting of Acheulean tools, which were hand-axes made by careful chipping of stones, the Ridgway Chainsaw Carvers Rendezvous utilizes the modern power of chainsaws to create detailed and often large-scale works of art. The answer to the question is therefore (a) Chainsaws.