Answer: A
Explanation: It makes the most sense because it isn't directly speaking about something, it is mainly summarizing the main idea. I'm not 100%, but that's the one I would choose if it were me. Hope I helped out a little!
5% of $20 is $1; 5% off $20 is $19
Answer;
(c) It can bond with other carbon atoms that are bonded to other molecules
Explaation;
-Carbon is the only element that can form so many different compounds because each carbon atom can form four chemical bonds to other atoms, and because the carbon atom is just the right, small size to fit in comfortably as parts of very large molecules.
-Carbon chains can bond with carbon rings to form very large, complex molecules. These large molecules can be made of many small molecules that are bonded together.