Although there are no options but this investigation is a COMPARATIVE investigation
Explanation:
Scientific investigations aims at satisfying a curiosity or a way of explaining natural phenomena. There are three types of investigations viz: descriptive, comparative and experimental investigations.
Comparative investigation is a type of investigation that involves collecting data on different organisms, locations etc for the sole purpose of comparing. It aims at confirming if there is a relationship between i.e. similarities/differences. In this question, two species of squirrels are being observed for their similarities and differences i.e. the aim of the investigation is COMPARISON. Hence, it is an example of comparative investigation
Explanation: The S phase of a cell cycle occurs during interphase, before mitosis or meiosis, and is responsible for the synthesis or replication of DNA.