Answer: B. Waste exchange
Sanitary landfill is a waste disposal process, in which the waste is isolated from the environment in a large site and degraded by biologically, physically and chemical methods.
Water exchange is not a waste disposal strategy instead, it is a process in ,which waste material is reused, recycled, reprocessed and repacked in other forms. This process is beneficial commercially, as the waste is being selled out.
Controlled incineration is a waste disposal method in which, the waste is converted into ash, flue gas and heat.
Deep well injection is a waste disposal process in this the liquid waste is deposited in the deep pit or site. Where the liquid seeps into the soil.
Therefore, on the basis of above information waste exchange is a correct option.