Now based on the structure of the dye borne molecule, determine the hybridization of the boron atoms. So remember we have boron here and it's connected to hydrogens, and these hydrogens are connected to another one.
If we just focus on one of the boron atoms, let's focus on this one. How many groups or elements is it connected to? It's connected to 1, 2, 3, 4 groups. Remember? If you're connected to four groups, meaning surrounding elements or lone pairs, then you are sp3 hybridized.
There had been at option C is our correct answer, right? So in this case our hybridization for each borne atom is sp3.