A city is located near a river and an industrial area. Over time, scientists observed the following:

i. Fish in the river showed bioaccumulation of a persistent chemical that caused neurological disorders in humans who consumed them.

ii. The air contained high levels of a gas that reacts with water to form acid rain, damaging monuments and crops.

iii. Soil had elevated heavy metal concentrations, leading to reduced fertility and toxicity in plants. On the basis of the given observations, pair each cause (i, ii, iii) with the corresponding pollutant (a, b, c) and answer the correct statement

a) Mercury

b) Sulfur dioxide

c) Lead