In an ethene molecule, the double bond joining the two carbon atoms is made up of one $\sigma$ bond and one $\pi$ bond. Which orbitals overlap to produce each of these bonds?
- A$\sigma$ bond: $sp^2$-$sp^2$; $\pi$ bond: $p$-$p$
- B$\sigma$ bond: $sp^2$-$sp^2$; $\pi$ bond: $sp^2$-$sp^2$
- C$\sigma$ bond: $sp^3$-$sp^3$; $\pi$ bond: $p$-$p$
- D$\sigma$ bond: $sp^3$-$sp^3$; $\pi$ bond: $sp^2$-$sp^2$