Choose all of the orbitals that can form a σ bond to the orbital displayed below (side-by-side, in the orientation shown).

s orbital

Explanation:

The orbital shown is a py orbital. py orbitals overlap side by side with s orbital to form a sigma bond. Looking at the direction of the Px and py orbitals, overlap of these with a py orbital can only lead to the formation of a pi bond.

However, the s orbital being spherically symmetric overlaps with py orbital in such a manner that a sigma bond is formed. The s orbital overlaps with one of the lobes of the py orbital.

Sigma bonds are formed by end to end overlap of atomic orbitals. It is the strongest type of covalent bond.

2b2t

explanation:

2b2t