Which of the following is true?

Statement I:Coarse particles PM10 can irritate the eyes, nose and throat and come from dust sources

Statement II:Fine particles PM2.5 are more dangerous, reaching deep into the lungs or the blood

ABoth statements I and II are true ✓ Correct

BStatement I is true

CStatement II is true

DNeither statement I nor statement II is true

Correct answer: (A) Both statements I and II are true

Explanation

Both statements about particulate matter are true, distinguishing coarse PM10 from fine PM2.5.

Statement 1 is right: coarse PM10 particles irritate the eyes, nose and throat and mostly come from dust.

Statement 2 is right: fine PM2.5 is more hazardous because it penetrates deep into the lungs and even the bloodstream.

The number in each label gives the particle's diameter in micrometres.

Smaller particles evade the body's natural filters in the nose and airways.

PM2.5 exposure is linked to heart and lung disease and premature death.

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