According to CPCB, which size of particulate matter are responsible for causing the greatest harm to human health?

2.5 micrometers or less in diameter 5.0 micrometers or more in diameter 10.0 micrometers or more in diameter 100 micrometers or more in diameter

2.5 micrometers or less in diameter

The correct answer is Option (1) → 2.5 micrometers or less in diameter