I believe it is A (Adenine)
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
Answer:
HeLa cells, like many tumours, have error-filled genomes, with one or more copies of many chromosomes: a normal cell contains 46 chromosomes whereas HeLa cells contain 76 to 80 (ref) total chromosomes, some of which are heavily mutated (22-25), per cell.
Explanation:
Classification systems previously were having very different goals than modern classification systems. If we look at old eras, scientists like Aristotle and Theophrastus tried to classify organisms on the basis of apparent characteristics, habitat and simple other traits.
Old classification systems had alot of errors and flaws. For example they classified fish and whale in one group because they lived in water, now we know fish is amphibian while whale is mammal.
So we can say that the goal o earlier classification system were just to make groups of organisms on the basis of External features.
Goal of modern classification system:
Modern classification approach was started by Linnaeus. It focuses more on biological delimitation and evolutionary histories than mere external characteristics. It organizes organisms in groups in such a way that grouping reflects their evolutionary relatedness. It is not just specie level but also focuses on sub-specie and population level classification.
Thus modern goal is better in many terms and is more reliable than old classification goals.
Hope it helps!