The wording of this is confusing. I think it’s A and B and I’m hesitant say that it’s also C but only if you know the mutation and the gene.
Also for A you would only know a partial sequence of the gene.
Cell Membrane because it transport nutrients into the cells and also transport toxic substances out of the cell .
The definition is the study of life
Genetic code - everyone uses same 4 bases. gene expression depends on many other factors
