What evidence suggests that glaciers may have carried stones to the Stonehenge site? A. The stones used to build Stonehenge all came from the same place in Wales. B. Some stones have markings that could have been caused by glacial activity. C. Some bluestones were present on the Salisbury Plain before Stonehenge was built. D. Bluestones were found in several places on a proposed travel route between Wales and the Salisbury Plain.