The correct answer is (c), World Toilet Day.
World Toilet Day is an annual observance on November 19, designated by the United Nations General Assembly in 2013. The day aims to draw attention to the global sanitation crisis and the importance of access to safe and clean toilets.
According to the World Health Organization, 2.3 billion people do not have access to basic sanitation facilities. This lack of access can lead to a number of health problems, including diarrhea, cholera, typhoid, and dysentery. It can also contribute to malnutrition, stunting, and other developmental problems.
World Toilet Day is an opportunity to raise awareness of the sanitation crisis and to call for action to improve access to safe and clean toilets for everyone.
The other options are incorrect.
(a) World Green Day is not an official observance.
(b) World Anti-poverty Day is observed on October 17.
(d) World Clean Water Day is observed on March 22.