Which describes pumice and obsidian? A. Both pumice and obsidian are coarse-grained intrusive igneous rocks. B. Pumice is a coar
se-grained extrusive igneous rock, while obsidian is a fine-grained intrusive igneous rock. C. Pumice is a fine-grained intrusive igneous rock, while obsidian is a coarse-grained extrusive igneous rock. D. Both pumice and obsidian are fine-grained extrusive igneous rocks.
