This depends a lot on the area in which the vacant lot is located, but in general it can be assumed that many plans would come up through cracks in the concrete.
It would be c. It can bond with other atoms through ionic and covenant bonds.<span />
You don't have any listed but here they are:
Protein - Amino Acid
Carbohydrate - monosaccharide
Nucleic Acid - nucleotide
Lipid - triglyceride
