<span>a. a substance that is naturally found in the brain</span>
A nucleic acid that carries the genetic information in cells and some viruses,
consisting of two long chains of nucleotides twisted into a double helix and
joined by hydrogen bonds between the complementary bases adenine and thymine or cytosine and guanine.
I think it’s the first one
Answer:
45 mg of caffeine in one cup of instant coffee.