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Question
An open-drain system is a breeding place for which of the following
Options
Flies
Mosquitoes
Organisms that cause diseases
All of these
Solution
All of these
Explanation:
In some places, there are open drains to dispose of the sewage. These drains can easily get blocked by plastic bags and can overflow. Therefore, the problems of smell, breeding of mosquitoes, flies and germs are encountered in open drains.
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