Answer:
b is the answer i am not sure.
Explanation:
Researchers have identified specific gene variants in the receptors that detect sweetness: TAS1R2 and TAS1R3. There is also high variation in the detection of bitterness. However, the story is more complicated than sweet taste, as we have 25 receptors that detect different bitter molecules
The molecular clock tracks down nucleotide sequences for DNA or amino acids that contain sequences of proteins. Scientists use this to deduce the time in history where life forms possibly have diverged. This technique is also known as a gene clock or an evolutionary clock.