The answer would be B. Cats.
Cats are the most advanced organisms between the options thus have the greatest amount of cell specialization.
By diffusion hope this helps
Answer:
The basic repeating unit of nucleic acids are known as nucleotides. A nucleotide consists of three distinct chemical groups, a 5-carbon sugar (ribose or deoxyribose), a nitrogen-rich base - (cytosine (C), guanine (G), adenine (A), thymine (T) in DNA or uracil (U) instead of T (in RNA), and phosphate.