Answer:
The correct answer is - normal oil tanker/shipping operations and urban run-off.
Step-by-step explanation:
Oil tankers are large ships used for the transportation of crude oil from one part of the world to another. These are responsible for major oil pollution and also contribute negatively to the environment and marine ecosystem.
Accidents of these tankers and cleaning the tankers, de-ballasting, and other normal operational processes cause the discharge of oil in the Ocean. Urban runoff is also one of the major human sources of oil pollutants in the marine ecosystem and affecting marine life.