Answer:
7) there is a theory that these animals can see the magnetic field of the Earth due to a compass like mechanism inside their eyes in order to navigate.
8) Earth's magnetic field is a result of the currents found inside the outer core that consist of electricity.
The correct option is D.
The model developed by Ptolemy has a lot of inconsistency and during the middle age additional explanation was offered for the claims made by the model. The model was very complicated because it was based on erroneous assumptions.
Copernicus model was simpler and some of his claims were correct.<span />
