Benzene contains six carbon atoms bonded in a ring. which best describes these bonds?

The benzene molecule has the molecular formula C6H6
.
Sometimes it is represented as a molecule with three doble bonds and three single bonds. But that does not count for the fact that experimentally all the bonds are equal: same length and same strength.

The six carbon bonds are equal because there is not preference for the valence electrons to attach to one or othe neighbor carbon, so at the electrons delocalize inside the molecules and form a uniform cloud around the six carbon atoms.

This is the effect named resonance and thas is why the molecule of benzene instead of being represented with some three single bonds and three doble bonds is represented with a circle (a ring) inside the molecule which represents an intermediate kind of bond shares by all the carbon atoms.

This structure was discovered (literally dreames as some texts tell) by Kekulé. 

 

C. 1s22s22p63s23p43d104s24p5