There is no much important of earth crust in human beings but for the people who r trying to be the scientist or discovers need to learn about it
I believe the answer is "D"
Iron rich minerals in rock pointed in one direction the switch to the exact opposite direction. I'd say that what supports this idea is that <span><u>Earth's magnetic field goes through pole reversals.</u></span>
Tum h o kon aur meri tarah kyun bani hui h o aur
