Read the sentences.

People around the world are concerned. They are concerned about climate change. The oceans affect the climate. It makes sense to study the oceans.

What is the best way to revise and combine the sentences to improve fluency?

People around the world are concerned about climate change, and the oceans affect the climate, and it makes sense to study the oceans.
People around the world are concerned about climate change. Given that the oceans affect the climate, it makes sense to study the oceans.
People around the world are concerned; they are concerned about climate change. The oceans affect the climate; it makes sense to study the oceans.
People around the world are concerned, and they are concerned about climate change. The oceans affect the climate, and it makes sense to study the oceans.