C. So it can travel from one part to another
I got D, C, A, B, C, B, D, C.
C (proteins) instead of D (nucleic acids) because if you look at a nucleic acid structure, you'll see that sulfur is not found in it. Sulfur is found in two amino acids (methionine and cysteine), which means it could be found in proteins since amino acids build proteins
B an obligate intracellular parasite
Simple....
this Na+
It means that it's positive..it has one less electron then a normal sodium atom would have..making it a cation.
Thus, your answer.
