What is responsible for the Magnetic Field around Earth? * O The Earth's crust
O The Earth's mantel
OThe Earth's molten iron core
O The Sun

The Earth's molten iron core

Explanation:

The Earth's magnetic field is mainly due to the convection current flowing in its molten iron core. It is considered to be a great conductor of electricity and is also dubbed as an "invisible river." If people were to study the magnetic field, they have to follow the movement of the molten iron that flows about thousands of miles every hour. The magnetic field is so strong that it can pass through the earth's core, crust and even reach the space (although it becomes weaker at this point).

i think the miocene epoch spans the time from 23 million to 12 million years ago.