What is the hybridization around the indicated oxygen atom in the following anion?

Question

Quizplus · Accepted Answer

The indicated oxygen atom in the anion has one lone pair and two sigma bonds (one to a carbon and one to a nitrogen atom). These three regions of electron density require hybridization to form sp2 orbitals. However, since this oxygen atom is also negatively charged (as it is in an anion), it also has an additional electron in a p orbital. Therefore, the hybridization around the indicated oxygen atom can be described as sp². Choice B is the closest to this hybridization. Option A is incorrect because it has an extra S1 orbital, and option C and D are too simplistic descriptions.

What Is the Hybridization Around the Indicated Oxygen Atom in the Following