The article states the following:
"While it's tough to say exactly how much plastic is in the ocean, scientists think about 8 million metric tons of plastic enter the ocean every year," notes the National Oceanic and Atmospheric Administration's ocean plastics guide. "That's the weight of nearly 90 aircraft carriers."
Why did the author use aircraft carriers as a comparison?
a
to suggest that airplanes can help in cleaning the ocean
b
to explain how they can transport the plastic in the garbage
c
to describe the large amount of plastic in the ocean
d
to inform about the many uses of aircraft carriers