The worldwide use of cleaner energy sources could result in what? which one is it? a rise in ocean levelsa reduction in acid rain
increased desertification in the sahel
decreased desalinization plants in the middle east

The best answer is reduction in acid rain.

Acid rain is rainfall which has been rendered acidic by pollutants  in the atmosphere.  This kind of rain is typically harmful to  forests and lakes.

The main cause of acid rain is human activities. The burning of fossil fuels such coal in electrical generating plants and crude oil products such as gasoline and diesel in car engine  releases  sulphur dioxide and nitrogen oxide into the atmosphere.

These compounds mix with water very high up in the atmosphere and form acid pollutants which  fall on the ground as acid rain.

 Use of clean energy will eliminate burning of fossil fuels and thus no acid rain will be produced.