The given figure shows a river and the types of land use on the sides of the river. The water quality of the river was studied by measuring the amounts of dissolved oxygen and ammonia in the water collected at sites X, Y and Z. The results are given below:SiteDissolved oxygen \[\text{(c}{{\text{m}}^{\text{3}}}\text{/litre)}\]Ammonia (ppm)X8.90.02Y0.30.62Z1.65.30 Which of the following is correct regarding this?

• A. Site X has the highest content of dissolved oxygen because of eutrophication.
• B. Site Z has the highest concentration of ammonia because of leaching of fertilisers from the nearby crop fields.
• C. Organisms such as algae and weeds will thrive at site Y, while very few fishes are found at site Y.
• D. Both (b) and (c).