'Fossils are preserved in sedimentary and not in igneous rocks'. Discuss.

Sedimentary rocks are formed by the deposition of sediments carried away by exogenous agents such as water, wind or ice. They are deposited in distinct-strata or layers.
Fossils in the form of leaves of plants, insects or some bovine animals and pieces of bones, shells or some hard parts of old living beings are deposited into the layers of the sedimentary rocks. In this way, fossils are preserved in sedimentary rocks.
On the other hand, igneous rocks are formed by the solidification of magma. They have no layers. They are hard and compact. Fossils cannot be preserved in such a hard and compact rock because fossils die out in the process of their formation. Hence, igneous rocks are free of fossils.