You are about to go to sea and adjust the magnetic compass．To expedite the adjustment at sea，in what order should the following dockside adjustments be made（）.

A.Flinders bar first，then the heeling magnet and spheres

B.Heeling magnet first，then the Flinders bar and spheres

C.Flinders bar first，then the spheres and heeling magnet

D.Spheres first，then the Flinders bar and heeling magnet