Answer:
The footprints at Laetoli were remarkably well-preserved because: they were made in an ash slurry that quickly hardened and were then buried by volcanic ash soon after they formed .
Step-by-step explanation:
Laetoli -
It is the archaeological site present in the region of northern Tanzania .
In this site the footprint of the ancient humans are preserved , because of the volcanic eruption .
Around 3.85 million years ago , a volcanic eruption took place , and due to the ash fall of the eruption , the foot prints of the ancients got preserved .