Answer And Explanation:
The following statement, "An intrusive igneous rock is fine-grained and forms when lava cools and solidifies" is b) False. An intrusive igneous rock is a coarse-grained rock, which forms as a result of the slow cooling of magma (molten rock) underneath the crust of the earth. Because this type of magma cools so slowly, it allows the grains and crystals to grow in size. It is extrusive igneous rock that is fine-grained, as a result of faster cooling. Extrusive igneous rock cools outside of the earth, when lava erupts. When the lava hits the air, the temperature difference is so great that the lava cools very quickly. This doesn't allow for the slow growth of grains and crystals within the rock, and it is therefore fine-grained. An example of intrusive igneous rock is granite, and an example of extrusive igneous rock is obsidian.