In order to understand the impact of climate change, a scientist collected measurements of average yearly sea surface temperatures from 1880 to 2012. His data is graphed below. What scientific question could be most accurately investigated based on the data collected by this scientist?

How did volcanic activity change with average sea surface temperatures?
How did melting arctic sea ice change average sea surface temperatures?
How did average sea surface temperatures change with increased aquaculture?
How did average sea surface temperatures change with time?