transporting oil over the ocean surface drilling for oil on the ocean floor polluting land with oil that reaches the oceans in runoff polluting air with oil that reaches the ocean in precipitation
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Just under half the oil that enters ocean water comes from natural oil seeps on the ocean floor. Just over half the oil in the oceans comes from human activities. Which human activity contributes the most oil to the oceans?
Possibilities:
- transporting oil over the ocean surface
- drilling for oil on the ocean floor
- polluting land with oil that reaches the oceans in runoff
- polluting air with oil that reaches the ocean in precipitation

transporting oil over the ocean surface