You have been given the basic connectivity of two boron compounds. Complete the Lewis structures by adding lone pairs and/or multiple bonds where necessary. If there is more than one possible structure, draw the structure that minimizes nonzero formal charges and fulfills the bonding preferences for each atom.

A. B2CO, with connectivity BBCO, as shown.

B-B-C-O

B.C2B2O2, with connectivity OCBBCO as shown

O-C-B-B-C-O