Lava rock is used in building roads, and question 4 options: pumice, a glass that comes from lava, is used for grinding and polishing materials they use pumice, a glass that comes from lava, for grinding and polishing materials

Your "pumice, a glass that comes from lava, is used for grinding and polishing materials".

This would be your correct answer, mainly because, after noting down a comma, we would (NOT) want to rephrase the topic, or even to restate the topic as well. And based on this, if we have noticed in our options, the first one, this sentence does not restate the topic after noting the comma.

Your "pumice, a glass that comes from lava, is used for grinding and polishing materials".

The Answer is "A"

Explanation:

They are different species