Atoms of which element can bond to each other to form chains, rings, and networks?
(1) carbon (3) hydrogen
(2) fluorine (4) oxygen

It's the Carbon. 
Because Carbon is tetravalent, and can have 4 bonds. 
While Oxygen is bivalent and can have 2 bonds, and fluorine and hydrogen is monovalent and can have 1 bond.

Hope this Helps :)

Okay well gravitational energy is matter forced by gravity making energy though the kinetic energy then the electric energy produces electricity from the kinetic energy and the kinetic energy gets its energy from the gravitational energy. was that the answer you wanted or something else?