Q: Q: Nitrogen is a very important element to living things, because it is part of nucleotides and amino acids that are the building blocks of nucleic acids and these?   A: | OPTIONS:
- cells
- lipids
- follicles
- proteins
A: proteins

Q: Q: In the first beaker, distilled water does not conduct a current because water is a what?   A: | OPTIONS:
- pure element
- solute
- magnetic compound
- molecular compound
A: molecular compound

Q: Q: The job of the nucleolus is to build what?   A: | OPTIONS:
- chromosomes
- electrons
- cells
- ribosomes
A: ribosomes

Q: Q: What can be combined with an amine to form an amide?   A: | OPTIONS:
- carbon dioxide
- ketones
- acetic acid
- carboxylic acid

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
A: carboxylic acid