The diagram shows the structures of four similar limbs in marine animals. Based on limb structure, which two species are most closely related? A. whale
B. shark
C. dolphin
D. Penguin

I would say the whale and the dolphin are the most closely related.

The answer is atmosphere. there are four spheres of the earth: 1. geosphere (from greek word 'geo' = ground), 2. hydrosphere (from greek word 'hydro' = water), 3. biosphere (from greek word 'bio' = life), and 4. atmosphere (from greek word 'atmo' = air). a magnetosphere is a region of space around astronomical objects controlled by the magnetic field of that object. through the process of elimination, since lightning is present in the air, it can be found in the atmosphere.