Answer: baked contact
Explanation: According to the principle of baked contact, an igneous intrusion bakes surrounding rocks, therefore the baked rock must be older than the intrusion.
Igneous intrusions usually possess very high temperature (magma) as they emanate from very deep region below the earth and may form different rock types based on their composition and cooling processes. However baking or metamorphosis (change) of existing rock will occur due to the temperature of the intruding magma. The principle of baked contact allows us to delineate that the change is caused by the magma intrusion as as such the surrounding rock is older than the intrusion.
