Select the incorrect statement regarding the rainfall with low $\mathrm{pH}$.

Select the option that correctly identifies $X$ and $Y$ in the given flow chart.

Read the given paragraph.

Soil $X$ has very poor water holding capacity, soil $Y$ is well drained and contains one part clay and two parts each of sand and silt. Soil $Z$ has excellent water holding capacity but is poorly aerated.

Select the correct statement regarding soils $X, Y$ and $Z$.

Read the given statement and select the correct option.

Statement 1: Extensive use of fossil fuels possess problem as it increases air pollution.
Statement 2: Fossil fuels release oxides of nitrogen and sulphur on burning, which consequently cause acid rain and smog.

The given graph shows the amount of pollutants in four rivers $P, Q, R$ and $S$. The river that can continue to support the most number of aquatic plants and animals is _____.