Fairly sure we go to the same hs but I put A. It might be c though. Not totally sure.
Answer:
Crystal size
Explanation:
The most obvious difference between extrusive rocks and intrusive rocks is crystal size. Because extrusive rocks cool quickly, they only have time to form very small crystals such as basalt or none at all. On the other hand, intrusive rocks grow larger crystals because they take longer to cool.
Tectonic activity that thrust mountains up from the ocean. floor because volcanoes come from the center of the earth and when the tectonic plates move it causes some of the lava from the inside of the earth to emerge and come to the surface where the ocean is and forms into an island (s).
They thought that it might keep them safe from harm.
