Task: Question Answering
Input (English): Process:  -Rock begins as magma from a volcano -The magma cools -Crystals form and the magma become igneous rocks -The igneous rocks break down into sediment -Become sedimentary rocks -If subjected to heat and/or pressure from plate-tectonic activity the sedimentary rocks become metamorphic rock -The metamorphic rocks melt -Become magma again.
 Question: What is the effect of less hard plant parts replaced by minerals on less igneous rock forming.?
Output (English): none