Which of the given option arranges the following sentences in the most logical sequence to from a meaningful paragraph?

Which of the given option arranges the following sentences in the most logical sequence to from a meaningful paragraph?
1. Without keystone species, entire ecosystems can collapse, leading to significant biodiversity loss.
2. The concept of a keystone species was first introduced by ecologist Robert Paine, who studied the effect of removing certain predators from an ecosystem.
3.Keystone species play a disproportionately large role in maintaining the structure and stability of their ecosystems.
4. For example, sea otters help regulate sea urchin populations, preventing the destruction of kelp forests.
5. This idea revolutionized ecology by highlighting how some species have a far greater impact on their environment than others.