Answer:
b. Succession is a gradual change to ocean communities
Step-by-step explanation:
An ecosystem can undergo changes in it's structure and composition over a particular period of time. This term is called ECOLOGICAL SUCCESSION. Succession is the gradual change that occurs to a community over time. Succession is of two types; primary and secondary succession.
According to the question, climate change and succession are causes of change to the ocean ecosystem. Hence, succession there represents the gradual change that occurs to the structural composition of ocean ecosystem over time.