Which of the following can increase the acidity of water bodies?a.Oil runoffb.Eutrophicationc.Sulfur discharge from an industryd.Hydrocarbon runoff from a refinery

The acidity of water bodies can be increased by:

a. Oil runoff: This does not directly increase the acidity of water bodies. However, it can indirectly affect it by blocking sunlight, which can affect photosynthesis in aquatic plants and decrease the amount of oxygen in the water. This can lead to an increase in carbon dioxide, which can increase acidity.

b. Eutrophication: This is a process where water bodies receive excess nutrients that stimulate excessive plant growth (algae, duckweed etc.). When these plants die and decompose, it can increase the amount of organic acids in the water, which can increase acidity.

c. Sulfur discharge from an industry: This can directly increase the acidity of water bodies. When sulfur dioxide is released into the atmosphere, it can dissolve in rainwater to form sulfuric acid. This acid rain can then increase the acidity of water bodies.

d. Hydrocarbon runoff from a refinery: Similar to oil runoff, this does not directly increase the acidity of water bodies. However, it can indirectly affect it by blocking sunlight and decreasing oxygen levels, which can lead to an increase in carbon dioxide and acidity.

So, the most direct contributors to increasing the acidity of water bodies among the options given are eutrophication and sulfur discharge from an industry.