Aelectrically balanced atom of chlorine has 17 protons in its nucleus. how many electrons does it have in its outermost shell?

An atom of chlorine from the periodic table has 7 electrons in its outer shell

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.

According to edgenuity, the answer is c.