Answer:
The correct answer is the second statement.
Step-by-step explanation:
The molecular clock refers to a procedure in molecular evolution that associate the time of divergence between the two species with the number of molecular differences determined between the sequences of DNA or proteins.
The more genetically associated, the shorter will be the separation time between the two species. Due to this, as clams and squid are more closely associated it can be concluded that these species look more genetically identical, and have evolved distinctly for a brief time duration in comparison to the clams and snails.