Which of the following exhausts, which is so ultrafine and microscopic in size that it is not even visible to the eye, makes up the largest proportion?

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PM-2.5 refers to particulate matter that is 2.5 micrometers or smaller in diameter. It is known to make up a significant proportion of air pollution and is a major concern due to its ability to penetrate deep into the lungs and even enter the bloodstream.

Which of the Following Exhausts, Which Is So Ultrafine and Microscopic