After reading the paragraph below, answer the questions that follow.
Consider the following marine community: Sea otters prey on sea urchins and therefore help maintain a healthy sea urchin population. Sea urchins prey on kelp. By helping to maintain viable sea urchin populations, the sea otters are also allowing enough kelp to grow and act as a habitat for other organisms.
In this marine community, the sea otter is a
◦ primary consumer.
◦ scavenger.
◦ producer.
◦ keystone species.