The correct option is C pollution of underground water with harmful chemicals
Municipal solid wastes include all the wastes generated from homes, offices, stores, schools, etc., that are collected and disposed by the municipality.
Sanitary landfills are dumping sites where solid wastes are compacted and then dumped into trenches or depressions dug in the ground. These trenches are covered with dirt everyday as new wastes are dumped.
A concern related to dumping of solid wastes in sanitary landfills is that harmful chemicals seep from the wastes buried in the landfills and pollute the underground water resources. Moreover, with increasing population and rapid urbanisation, the rate of waste generation has become so high that most sanitary landfill sites have been filled up.
Burning of wastes in open dumps results in the emission of harmful smoke due to incomplete combustion of the wastes.