Instructions: In this task, you are given a paragraph, and your task is to construct a question from the given passage. Construct question in such a way that (i) it is well explained in the paragraph, (ii) the words may/may not be present in the paragraph, (iii) it should start with what/how/describe. Avoid creating a question that (i) is just relevant to one or two sentences, and (ii) not relevant to passage. 
Input: Magma rises to the surface during a volcano. The magma undergoes changes in temperature. The magma undergoes changes in pressure. The magma cools. The magma solidifies. The magma crystallizes. Igneous rock is formed. 
Output:
How does igneous rock form?