Rainwater picks up carbon dioxide from the air and as it percolates through the soil, which turns into a weak acid. This slowly dissolves out the limestone along the joints, bedding planes and fractures, some of which become enlarged enough to form caves.
The answer is C. thousands of galaxies
because<span> Hubble found 10,000 of galaxies just by observing one small little area in space.
So, it has to be thousands.</span>
Forest soils because forests cover most of the land but not as much as the ocean