Noise is defined as ........

Snow blindness is caused by

Prolonged water logging in an agricultural field is likely to create the problem of:

$D.D.T.$ is a/an:

Air pollutants:
$I.$ Cause injury to all living organisms.
$II.$ Reduce growth and yield of crops and cause premature death of plants.
$III.$ Affect the respiratory system of humans and animals.
Which of the statements given above are correct?

What does '$X$' represent in the given figure?