The term biosphere is used for the zone of the earth where life exists:

Green chemistry refers to reactions which . . . . . .

What is the greenhouse effect?

Eutrophication causes:

$A.$ Ammonium salts produce haze in the atmosphere.
$B.$ Ozone is produced when atmospheric oxygen reacts with chlorine radicals.
$C.$ Polychlorinated biphenyls act as cleansing solvents.
$D.$ 'Blue baby' syndrome occurs due to the presence of excess nitrate ions in water.
Choose the correct answer from the options given below:

Match the following List-$I$ ($F^-$ ion concentration in drinking water) with List-$II$ (Effects on humans):

List-$I$	List-$II$
$(A)$ $< 1 \ ppm$	$(i)$ Harmful to bones
$(B)$ $> 2 \ ppm$	$(ii)$ Tooth decay
$(C)$ $> 10 \ ppm$	$(iii)$ Brown mottling of teeth

Then the correct match is: