Glacial striations gouged into bedrock allow geologists to understand

The direction of glacial movement, is the right answer.

Explanation:

Striations are cuts appeared on a rock exterior by rock remnants pierced into the foundation of a shifting glacier. Rocks deposited in the surface of the glacier scrape adjacent the recently opened bedrock and leave behind line-shaped scratch marks called glacial striations. The direction of scratch marks informs us about the direction in which the glacier flowed.

Glacial grooves and striations are channeled or scraped into bedrock as the glacier flows downwards. Rocks and rough sand get confined under the ice of the glacial and abrade the area as the iceberg pulls and pushes them along.

answer; consonant;